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Garmin's StreetPilot c320/c330/c340>  A Simplified Car Navigator
GPS Product Review
by Joe Mehaffey
Release 7 updated,   22 November  2006


                       c320 GPS unit                                 Daytime  Map Colors  3D View Mode          

More StreetPilot c320 Photographs

Where does the c320 fit in Garmin's Product line?
The StreetPilot c320 is, we think, Garmin's answer to the TomTom "Go" and the Magellan RM300 .  Garmin rates it as a "Beginner's GPS Car Navigator" and in that we agree.  The c3x0 ( when we refer below to the c3x0, we are referring to features present in BOTH the c320 and c330 models)  is extremely simple to use, easy to input address and other data, and has a limited number of features so as not to confuse people unfamiliar with GPS equipment.  What the c320 is NOT is a replacement for the much more "feature rich" StreetPilot 26x0 models.  The c320 offers a simple to operate, capable car navigator with the essential features of other car navigation units but with few of the "frills, bells and whistles" that many users have come to expect from Garmin.  As a comparison,  the c320 appears to be competing with the reduced feature set and operational simplicity found in the typical OEM car navigation system.  The c330 is essentially the same unit but for the c330 having built in 2.2Gbyte Hard Drive for the map memory so the user has no maps to load.  The c330 can " operate  right out of the box".  The new c340 is the same as the c330 with the addition of capability to accept input from Garmin's GTM10 RDS-FM radio receiver so as to be able to automatically route you around road problems in cities where RDS traffic radio is available.   The c340 (unique in this group) allows the user to input 3rd party provided CSV files with locations of speed cameras, school zones, and other traffic hazards. The SP c3x0 models now can operate with Garmin's new CUSTOM POI LOADER software.

Note that the c320/30/40 are, in essence,  PURECar Navigators.  They have a built in speaker (not in the cable assembly) and provide among the best audio and routing directions using Garmin's version of Naqteq road maps.   Don't expect any hiking, marine or geocacheing features from these units.  We examined the screen brightness and readability in sunlight on a car dash and found it to be "readable" but these models  had considerably less contrast and readability than the StreetPilot 26x0 models,  was a little worse than the Quest models and a bit better than the TomTom "GO".  Garmin tells us that there are no plans for the c320/30/40 to change over to the much brighter and easier to read screen used in the c550.   (See GPS readability report HERE.)  The SD card capability of the c320 puts it on a par with the Magellan RoadMate 300 and both can (currently) operate with the available  1GByte SD card map memory.  (All USA and Canada requires perhaps 2 Gbytes.)  However the c320 has quite an advantage over the RM300 in that in the c320  a) the maps are MUCH easier to install and b) map sections are seamless with driving and no manual intervention is needed as you move from one map area to another.  Garmin has a special version of CitySelect especially designed for the c320.  This version offers "state sized map chunks".  That is,  the smallest "chunk" of map you can load is one state.  For example, if you have a 128meg SD map memory card and you want to load, say, half of California and half of Nevada, you are out of luck.  There IS a workaround for this.  If you have an older version of CitySelect 6 or CityNavigator 6, you  can load maps from these into the c320 and that older (non c320) map version will allow you to select much smaller map areas. 
The c320 comes with a 128meg SD memory card and can accept SD memory cards up to the (currently available) 1GByte size.  (Coming in 2005 is the 2Gbyte size SD card.)

The c320 has a built in rechargeable battery pack that is recharged via the built in mini-USB receptacle or when the unit is plugged into its suction cup equipped automobile cradle and plugged into an operating 12vdc cigar receptacle.  An adapter is furnished to operate the unit from a) 120VAC power via a "wall wart" adapter (Deleted from kit beginning about June 2005).  b) 12volt cigar lighter plug, and c) it also automatically charges when the c320 is connected to a powered up laptop or PC via the power wiring in the USB cable.    The battery life for the c320 between recharges is rated by Garmin at about 8 hours. 

What comes in the C320 kit?
The c320 comes complete with all of the parts necessary to mount the unit to your windshield and plug it in and operate in your car.  Included are:  a) The c320 unit itself,  b) a suction cup mount to attach the GPS to your windshield glass,  c) 120vac to 5vdc power module for use when programming or setting up your unit in the house,  d) 12/24vdc automobile power cable,  e) user manual,  f) special c320 version of CitySelect 6 and related map unlock documentation.  The c3x0 units have a built in PATCH style antenna which works very well.  In fact,  the RF sensitivity of the  c320 unit we have is superior to most of the GPS equipment we have tested.  As a result, I can say that it will be unusual to need an external amplified antenna except in exceptional circumstances such as use in trucks with cab overhanging bodies as on some campers.  The c3x0 units CAN accept an external amplified antenna if needed but one  is not included in the standard kit.

Unfortunately  (for the kids), Garmin did not choose to put any games in this model.   The c3x0continues Garmin's marketing plan of "Market Specialization" which means to position various models for specific functionality and leave out specific features of interest to a specific group of users.  For example,  our "ideal" general purpose GPS receiver would have a color screen,  CF or SD card memory,  full marine and hiking feature set,  full car navigation capabilities and a rechargeable battery pack with external power capability.   Lets see how the c3x0 fits these requirements.

The c3x0 screen is a medium brightness  TFT daylight viewable-with-backlight screen.  However, the c3x0 screen is not nearly as readable in bright sunlight as compared with the SP26x0 models.  c3x0  has no marine feature set  and no hiking features are provided.    The Lithium Ion battery  is sealed into the package and is not normally user serviceable.  HERE are some comparative photos of the c320 screen with some competitive models.

The  USER INTERFACE is similar to other Garmin units which use a touch screen for data input,  However, in the c3x0, there are just two controls other than the touchscreen.  These are the ON/OFF push button and the "sliding fingertip" volume control.  Both are on the right side of the case alongside the USB cable connector.  There is also a three pin power connector that mates with the snap-in window mount.  No RS232 NMEA data output is provided.   The 12vdc cigar lighter power cable is integral with and attached to the windshield mount.     Like  the SP2610 and Quest, the C3x0 automatically turns ON and OFF with the power application from its external power cord. A switch is provided to turn the unit on and off manually as desired.  c3x0 seems to be designed  to provide "ordinary non-technical people" with a high performance SMALL SIZED, LARGE COLOR SCREEN GPS CAR NAVIGATOR.   The c320 is straightforward to use, and we think the manual is a bit better than average.  Still,  there is no substitute for a few hours of  "playing around" with the unit in consort with the manual for quick learning and  discovery of available features.  

The features of the c3x0 make it a fairly direct competitor to the Magellan RoadMate 300 and to the TomTom GO..  A detailed comparison of the features of the Quest, c3x0, and SP2610/2620 models can be found HERE.   Our Magellan RoadMate 500/700 review can be found HERE.  (Our review of the RM300 should be available in June 2005.  The StreetPilot 2610/2620 review can be found HERE.  As stated before, None of these units can provide the capabilities of a full featured hiking and marine oriented handheld unit.There is a list of the major features NOT present in the c320/c330 as compared to the StreetPilot 2610/2620 HERE.

Street priced at about $600 or less, (Check Latest Prices Here.) the c320 is a medium  priced Automatic Car Navigator..  Street Price of the C330 is about $800 or less.   While the c3x0 is not a full featured unit like the SP2610/2620,  it does provide guidance in the same class and equally good maps with even the most expensive of todays car navigators.   The "non-technical user friendly" ease of use, ease of map installation (and even no map installation at all on the c330) make both units recommended for the non-technical user.

What about map loading and Map Memory?
StreetPilot c320 uses a  USB data interface for map loading and data input/output. But you CAN also load the maps even faster on the c320 (only) if you remove the SD card and use an SD card writer with your computer to load maps into the card.  Map selection,  map build and download for a full 1 Gbyte SD card took about 2 hours via the USB cable of which only about 15 minute was "human time" all up front.  The c320 can be told to shut off at the end of map loading if you wish.  Also, while map downloading is occurring, the C320 battery is being charged via the USB cable from your computer.   The c320 has no standard NMEA input/output capability.  The c320's furnished 128 megabyte SD map memory will hold approximately the states of Florida, Georgia and South Carolina with a little of Tennessee thrown in.   The 1Gbyte SD card held about half the USA.  In Europe, we find that the c320's 128megs will hold about half the UK or a bit less than half of France.  You can put part USA, part UK, and part France maps into the unit at the same time if you wish.   c320 comes with a routeable basemap for your region just like VISTA/LEGEND COLOR (LC/VC), QUEST and StreetPilot models.  Also packaged in the c320 (only) Kit is the CitySelect Map system for the USA and Canada (or other region of the world for the area where you buy your c320).  The North American model c330 comes with a built in 2.2 Gbyte Hard Drive on which are preinstalled maps for all of the USA and Canada or for all of Western Europe (European Models).   Note1:  Garmin will not confirm the 2.2 Gigabyte size, that is Joe's guess. 
Note2: As of May 2005, you can install other compatible Garmin CitySelect Maps in the c320 but not in the c330.
Note3:  Garmin advises us that coming production models of the c330 (as of about June 2005) will have an SD Slot so that the user CAN load maps other than CitySelect6 on the c330. 

With the Navteq brand maps,  users will have the most detailed highway and residential street level GPS uploadable maps available for the USA today. The USA coverage area for furnished  Navteq maps is the entire USA and ALL of  Canada.  c320 allows a user to automatically route using both the CitySelect maps and/or the Base Map. Thus, with a "routeable base map", you can automatically route from an address in New York City to San Francisco with only CitySelect map sections for NYC and SFO loaded. The base map will provide information (and "road lock") for all highway routing between metro areas.  Garmin provides the only autorouting system that I am aware of that can do this sort of intercity routing without the need to load intermediate maps as you go from one Navteq region to another. Garmin is shipping the c330  with its new CitySelect 6 for the c320 map system preinstalled on a 2.2 GByte hard drive so no basemap is needed.  (CitySelect automatic routing maps are only available for the USA, Europe, South Africa and Australia as of October 2004.  However, Garmin Licensees are providing maps for a dozen (plus) other areas such as Chile,   etc.)  Check Garmin's Cartography site for a list of countries and vendors to contact.   Note: Garmin tells us that AT THIS TIME the c330 can ONLY be equipped with USA/CANADA or European maps.  Note:  Jack and Joe recommend purchasing the c320, buying a US$75 one gigabyte SD card (or 2gigabyte when available) and load the states you need and enjoy a lower cost plus twice the battery life as compared with the c330.  The added flexibility of being able to simultaneously load maps from parts of the USA/Canada, Europe, Australia, South Africa, parts of the Middle East and etc., give the c320 versatility not found in the more expensive c330 at this time.

This review was done using copies  of CitySelect 6 USA.   With the supplied 128meg SD map memory you can load detailed maps for a fairly large area.  However, I suggest that at least 512megs of map memory will be needed by a great many people.  Also,   the lack of a basemap  can be frustrating if you take the unit overseas as (our) tours cover a lot of ground and this usually means that we have to load maps several times if we only have 128megs of map memory.  We like Magellan's scheme which offers basemaps for all parts of the world that can be loaded into many of their GPS Car Navigator products.  However, a 1GByte SD card overcomes a lot of our objections as it is possible to load about any maps you would ever need on a tour to one 1GB SD.  Note:  There is no provision to load maps other than from one map type (such as CS6) and then be able to switch between them as is provided for on most other Garmin units.

Other maps compatible with c320  include: CityNavigator (Navteq Maps, the best GPS routeable maps available in areas covered),   We understand that  Roads & Recreation, MapSource, USA Topo, and WorldMap CD ROMs also work with c320, but without automatic guidance.   Probably most other Garmin maps will load and operate,  but Garmin supports only the maps that they list as compatible in the c320 specifications.

Route Quality is rated "good"  and in fact routinely gives routing the same as I would have chosen.  Sometimes the route generated is just OK, but after all, these devices are just machines and they are operating without the local traffic knowledge an individual user has. The downside for c320 as compared to the $3000 models is that many of the more expensive models have some sort of "dead reckoning" capability to permit navigation to continue for short intervals when signals are lost. Such signal loss can happen in city canyons such as NYC, Chicago, LA, and London where high rise buildings can block the satellite signals.  In fact, c320/2610/2620 do have "poor man's dead reckoning" in that when signal is lost, the GPS assumes you continued on your last heading and speed for up to 30 seconds. This 30 seconds covers most ordinary driving.  The real dead reckoning capability is available in the Garmin StreetPilot 2650/2660 and in a few other units such as the VDO Dayton MS5000.  The 2650/2660 will require a connection to the automobile speedometer output and backup light to be able to function in dead reckoning mode.  Without these inputs, it will function same as the c320/2610/2620.  Note: The 2650/2660 require connections to the speedometer and backup light signals.

The new c320 version of CitySelect 6 provides "map chunks" in the form of the 50 states.  Selecting individual "map chunks" when you want to load maps can take a bit of time.  MapSource  has a new, though slightly hidden, feature to make this EASY.  With the map tool selected in CN6, simply hold down your mouse button and drag to put a "box" around a specific area of interest.  Boxes can overlap and be various rectangle sizes so you can use them multiple times in selecting your desired map chunks.  If you want to DEselect an area,  hold the CTRL KEY and simultaneously use your mouse to draw the box and you will deselect any map chunks in the covered area.   You can go to this link and watch the MapSource tutorial, which will explain how the new LARGE AREA map selection feature works. 

Automatic ROUTE GENERATION with  c3x0's  high speed processor is quite fast.  The calculation of a 400 mile route  usually takes about 5  seconds.  This compares to close to a minute with the SP-III.   One trial route from Atlanta to an address in Maine took about 1.5 minutes with the SP-III and about 10 seconds with the c320  which seems extremely fast by comparison.  Off Route, reroute recalculation with the c320 typically takes a few seconds and it generally tries to take you back as quickly as possible to your ORIGINAL route.

The c3x0 models do NOT offer the capability to create a route on the PC and download it to your GPS for execution.  You can create waypoints and download these to your c3x0 for use as destination waypoints.  There is no provision in the c3x0 for VIA waypoints as are available in Garmin's other Car Navigators..

Note: As of this date, NO OTHER map products (from alternative vendors) can be uploaded into Garmin GPS receivers except those offered by Garmin and Garmin LICENSEES for the purpose.  (See Garmin Website's Cartography section for a full list of map offerings.)  This same proprietary relationship exists for other vendor's consumer GPS products as well.

What's new in the c3x0 models?

The c320 kit contains:  GPS with speaker built into the unit,  power cable, USB data cable (for memory and data load and Garmin Data Protocol output), suction cup Dash Mount Bracket,  AC power module for use in loading memory,  CitySelect 6 CDROM, and  Manual.  The c330 is the same but without the CitySelect CDs because map software comes fully loaded and ready to go in the c330.

Like all modern car navigators,   c320 gets rid of almost ALL of the bad effects of GPS measurement error that bother many people.  When you use CitySelect, the c3x0 will "lock" your vehicle track to roads as long as you  travel on the road.  This feature does not operate with MapSource R&R, USA Topo, or WorldMap among others.  Automatically generated routes using CitySelect or CityNavigator maps "rubber band" to the roads in the route. Once in a great while, you may find an isolated road segment where the map is so far off that road lock will jump off the road, but it is rare.   

Another useful feature with CS/CN  maps is that (when not in guidance mode) all approaching cross street names are displayed prior to arrival. 

We found the  audio and visual guidance directions very satisfactory.  c3x0 automatically varies its "turn here" warning time to give you more warning time at high speed than at lower speed. A typical audio/visual sequence would go something like this:


The c320/c330 (uniquely) does not normally pop up a window to show you a turn.  Instead, a thick pink line shows your project route on the map and an upcoming turn is announced on the audio and shown as a thick white line with arrow on the road and through the turn. See screen image (22A)  HERE for example.   AutoZoom brings details of the turn into view as the turn is approached.  On the right bottom of the map display is current speed (or when routing, distance to turn), middle bottom is a MENU key and left bottom is TIME TO GO. See screen image (22A) HERE for example.  At any time, you can press the "speed/distance to go" display window and get the latest directions in audio form with a pop up text window as well.  (Note: Unlike other Garmin car navigators, the volume control and speaker are in the side of the GPS unit itself.)  Full screen image AND voice directions are available from the c320/c330 on either internal battery or external 12vdc power. 

Another screen display is the trip computer.   Data displayed include:   Direction of travel, current speed,  miles to go on route, miles traveled,  overall average speed,  moving average speed,  maximum speed,  total time, moving time, and stopped time.  There are no user adjustable data fields on the trip computer screen or elsewhere in the c3x0 units.

Another available screen is the written description of "next turns".  This is accessed by pressing at the top of the touchscreen on the legend showing the current street being traveled. 

AUTOZOOM zooms the screen in and out automatically as you approach turns so you  have time to make decisions.

Route selections for CAR/Motorcycle, Bus, Truck, or Taxi, or Emergency vehicles are provided so you can be properly routed depending on your vehicle type.

CitySelect now features about five million "points of interest" in the USA.  These include: Food and drink, Lodging, Attractions, Entertainment, Shopping, Services, Transportation, and Emergency and Government. In our area,  there were a few restaurants we had not known about and a  few  prominent ones  are missing.  Likely this will always be the case.   Despite some obvious updates and additions,  the restaurant listing  appears to be about 2 or more years old.  Listed "Attractions" include theme parks, museums, schools, parks and such.  The listings were quite satisfactory though the placement of a particular restaurant or gas  station might vary plus or minus a few hundred  feet (once, half a mile) from the actual location.  This feature could be very handy in a strange city.  Do not be overly surprised at imperfections such as your favorite restaurant being missing or some restaurant that is out of business for 5 years still being in the POI list.  The POIs come from a multitude of data sources and it is simply impossible to insure accuracy with the resources available for the task.

The user can give the GPS a Street Address or Street Intersection or select one of the, for instance, Restaurants in the accessory map data base module and it will LOCATE this address or location automatically and plot it on the map screen.  The c3x0 can then automatically create a "turn-by-turn" route to this destination from wherever you are. This is a very useful feature and it has worked very well in our tests. Be prepared for a few well known items (such as my local library) to be missing from the "attractions" list. Still, if you are unfamiliar with an area, what IS included will be quite useful.

Are the 128 megabytes of SD card MAP MEMORY enough?
The "comes with the kit" 128meg SD map memory will be enough for many users.  
The fact that the full USA coverage basemap can be used for navigation on interstates and major roads and highways mitigates the need for full coverage of the high detail maps-- but... Personally we do like to have the full detail maps loaded just in case we need services or a good restaurant while on the interstate highway.   Still, if you rarely travel more than your own state plus one to four other nearby states, (on average), c320's 128 megs of SD map memory will get you there just fine. 
When you need complete detail for a PARTICULAR city or rural area you are going to visit, you can load from your laptop, or other IBM type Personal Computer, high detail maps from CitySelect 6 into the  memory using the furnished USB cable.   Note that with the c320's special version of CS6, you MUST load a full state map at one time.  You cannot load smaller map sections as you can with the standard CS6 (MAC users note:  Users report mixed results trying to load Garmin maps using a MAC.  Count on needing a PC to load maps on the c320 to avoid disappointment.)

The basemaps in the c320/c330 do not allow the user to route to anywhere ON the basemap.  However, if you are going from, say, Chicago to San Francisco and back to Miami with a stop in Denver, you might load detailed maps for the four urban areas of interest and let the basemap be your guide THROUGH other areas and still have lots of empty memory in your user map cartridge for other areas. The unit automatically transitions from the basemap to the detailed maps when the detailed maps are available and back again as you move out of the detailed map areas. While it is quite easy to load new maps from a laptop computer into your c320,  having a basemap for the entire USA and Canada that will route you between towns and cities can eliminate the need to load highly detailed maps for intercity travel. That said, DO NOT expect that the basemap is as accurate as the CityNavigator maps from Navteq. There will be some areas where the map error is larger than 150ft and the c320  will think you are offroute and will recalculate. This is a minor irritation for some people but if you just ignore the problem when it rarely occurs, things work out fine.

  What are the Technical Specifications of the c320/c330?

Specific Questions Answered: 

Feature and Function Highlights 

We do not recommend  c320 for hiking or marine activities due to its reduced feature set optimized strictly for automobile use.

The  c320 used for this review includes no basemaps outside the Northern part of the Western Hemisphere.  The basemap of North America  includes maps of USA interstate,  national, primary and secondary state highways, cities, larger towns, waterways, rivers, and coastlines and high population parts of Canada and Mexico.   (Note: See Garmin Base Maps description for more information on Base Map content.)  Base Maps are included  in the c320 's internal memory while USER Uploadable Street Maps on CD ROM provide street level or topo detail of user selected areas which are loaded to the 128meg to 2048meg (2GByte) SD memory cartridges.  Garmin (unlike some Magellan models) provides no capabilities for the user to change from one basemap to another.

Additional  features include:

The trip computer works similarly to other late model car navigators.  With c3x0,  you will notice that  when you come to a stop, the estimated times do not go to infinity, but hold a realistic value. The GPS calculates estimated times based upon road classes in your Route and modifies the estimation by your actual speeds on the various road classes. It also computes the actual road distance between turns (waypoints) instead of using straight line distances.  The results give fairly accurate estimated time to various points, even when using different road classes, like traveling on the freeway, and then exiting later on some local roads. Your estimates will not only be based upon your current highway speed, but by the combination of speeds you are using, or will be using on the various road classes.  We note that the arrival time  was within 10 minutes on one 400 mile highway drive we made after it "learned" our driving speed habits.  Usually it slightly underestimates the time principally as a result of unexpected traffic congestion which randomly occurs.

The GPS has the standard HOST mode which allows  the upload/download of waypoints only. The  external power/data cable is different from other Garmin GPS equipment including StreetPilot models.  However, the unit charges when connected to a laptop or other active USB port   It is doubtful that as of October 2004 any third party software is available to interconnect with Garmin's USB data port on the c3x0 and it would not be very useful if available..

The data fields, on the main display screens  ARE NOT user configurable on the c3x0 models.

CityNavigator's  Find-an-Address feature includes: Recent Finds,  Cities,  Exits, Addresses,  Intersections, Points of Interest, Food,  Lodging, Services,  Entertainment, Attractions, Shopping, Transportation,  Emergency and Government and Waypoints.  However,  some  of  the locations  of restaurants, hotels, etc. are misplaced by considerable distances.  Since the data is at least a year old,  some businesses are "missing" but overall the data is quite accurate and useful.

When not routing,  a "Driving Status" line on the top of the Map display indicates such information  as "Driving South on Roswell  Road".  This can be quite useful in cities where you don't exactly know which street you are on. Also as you are driving, the name of each approaching side street is displayed allowing finding side streets in the dark.

Brightness on the c3x0  does NOT automatically adjust for ambient light conditions like the SP26xx models.  However, automatic changeover from night to day mode as needed is provided.

Datums- The c3x0 supports the standard WGS-84 datum only.

User ICONS are NOT supported in the c3x0.

The price of the c320  includes:  GPS unit, power cable, CitySelect 6 CDROM (full USA/Canada license), Suction cup mobile mount,  USB data interface cable,  AC 12vdc PSU and cradle for auto use, manual, quick reference guide and other documentation.

The c3x0 operates from  external power in the range of 11 to 24 volts DC or from its internal LiOn battery.  Battery life on our c320 unit was about 6 hours.    The LED backlit display lighting has a rated design life of 100,000 hours.  The c3x0  shuts down when power is removed and  turns back ON when external power is restored. (Assuming the power was ON when the external power failed.)

A special mobile power cable is supplied with c3x0 . The  power cable used is NOT the same as any prior Garmin cable connector. You will need the (industry standard) USB DATA cable (furnished) to load maps into your and/or to upload/download routes/waypoints/tracks to your personal computer.

The external antenna connector, a MCX coax jack,  is located on the right rear of the unit.  The MCX  jack is powered (nominal 2.7 volts no load in our unit) and has a current limit rated at 25 ma  to protect the unit from shorts on the antenna cable. The normal antenna is built inside the unit and is not removable.   The Garmin GA-27C (Garmin part number 010-10052-05) amplified antenna, some from  Tri-M, and other 2.7 volt rated antennas  work with the c3x0.  We believe most  3 volt antennas will work as well.

The c320 does not support NMEA-0183,  DHCP or RTCM.   Garmin has included an abbreviated version of its standard HOST MODE and no other option.

The maximum altitude rating is 60,000ft and speed maximum is 999 knots.

Subjective Observations of Performance

I have tested the c320  on  roads and highways of North Georgia and Atlanta including several interstate trips.   We used CS6  for our tests.  Our c320 has worked properly almost all the time in our tests.  Only twice in about 1500 miles of driving, the unit gave faulty turn directions.  In these instances, our SP2610 (running simultaneously) did not err.  Generally, tracking worked well but as is normal, we occasionally lost lock momentarily in cities and in deep mountain valleys.  

There was never a failure to lock to SVs in a reasonable time which was usually about 15 seconds.

The SP performed on a par with other GPS units in every test for lock stability,  multipath performance, re-lock after an underpass, and ability to suddenly change direction without loss of lock.

We note that all Garmin GPS  models including the c320 have a form of "dead reckoning" for moments when signal dropouts occur. For instance, if the  is tracking along and just before a sharp turn you invert it and block its antenna, it will continue to track straight for about 30 seconds.  It also provides a very good data smoothing filter to throw out random fixes that are way off track. This results in an exceptionally smooth track on a moving map display.  Even with this filter,  there was no overshoot apparent during quick stops, sharp turns, and similar maneuvers when normal continuous tracking was taking place.

c3x0  performance under tree cover and city canyon conditions was about the same as the earlier SPs, G-V, G-II+, G-12XL,  and we rate that as very good.

We found the display controls exceptionally easy to learn and use.  The overall  system is  suitable for car navigator use by users not familiar with computers and computer technology.  This is especially true of the c330 which comes with maps already loaded.  What the average user has to work with on a day-by-day basis is very simple to understand and manipulate.   The menu system and arrangement is generally quite intuitive and easy to learn to use.  

Since the c3x0  exhibited essentially identical tracking performance with other Garmin units in our tests,  we did not perform the extensive field trials we made with the G-12XL,  EE, and others.  For more information on tracking results with our testing of the G-12XL, and the G-II+, etc., see our reviews at:


Our overall impressions are that the is Garmin's version of a  low cost Automobile Navigation System with limited feature set but with exceptional ease of use. We consider the c3x0 to be "very good"  in the low price class of Car Navigators.    (Check Latest Prices Here.) We think the  is a good product for the money.  

*Problems and Quirks noted in using  the c320
1) The map display readability is the worst problem of the c3x0.  The road on which the route is moving is displayed clearly.  However, cross streets and nearby streets are shown on the routing map with such low contrast as to be unreadable in bright sunlight. In fact, the entire display becomes extremely difficult to read in bright sunlight in all the c3x0 models.  Garmin has indicated no plans to upgrade the display on these models.  (Note: The C5xx models DO NOT have this problem and in fact have a much brigher and more readable display.) We find that named cross streets and nearby streets and landmarks to be extremely useful in showing exactly where you are at a given time.  We sorely missed this ability on the c320.
2)  As with other Garmin Car Navigators,  entering street names can be a problem.  You might know a street name as AC Lewis Road, or A C Lewis Road  or Baywater or Bay Water or Baewater or Arbor vitae or Arborvitae and the spelling may/may not match the local convention.   The user MUST spell it like the Garmin/Navteq database or the address cannot be found.   This can lead to not being able to find a street that you know is there. 
Navteq tells us that their convention is to run initials together and use caps, so you might try that if you get stumped with a street name with initials.  For a street address with a highway number, try just the number such as 32 (not HWY32).   
3) We sorely miss the INability of the c320 to allow the user to select display parameters from a list as in other Garmin models.  However, the c3x0 units are intended for a "low tech", unsophisticated customer and the design goal was to keep the user interface to that absolutely essential for car navigation. 
4) POI groups are incomplete (though they are VERY VERY  helpful).  As examples: I find that some post offices and libraries in my local area are not included, but MOST are.  I am afraid relief here will be forever in coming.
On occasion, we see the router generate "funny routes" such as taking a busy numbered federal highway instead of a nearby freeway.   Overall,  the  performs as well as other Car Navigators we have used.  Garmin tells me that these problems WILL be looked at if users will go to and fill out the report form.  Lets ALL do it!     Overall, I must say that every edition is better than the one before as to routing problems.
6)  The c3x0 uses a slightly different algorithm for navigation than the SP26x0 models.  At times, I found the display and audio combination directions to be confusing and even misleading.  On a trip of about 1500 miles, on at least four occasions (in the dark each time) the instructions were misleading (or unclear) enough for me to make a wrong turn.  The 2610 running at the same intersection provided substantially easier  to interpret instructions.  After switching to the SP2610 unit in the dark on this trip, I missed no more complex turns. 

Which GPS do I like to use when I go on automobile trips?  The StreetPilot 2610/2620. I must add that the c3x0  is a great unit when small size and lower cost are part of the equation.  It seems ideal for the person who is "computer hostile"... That said,  I personally prefer the SP26x0 units because of their MUCH more capable and flexible feature set and because of their much more readable display screen.  

If anyone has any additions, ions,  suggestions,  error corrections other comments, please feel free to Email.

Joe Mehaffey