1) Generally speaking, GPS signals are the same over
the entire globe and so any GPS will be able to compute its position anywhere.
2) If you intend to buy a NON MAPPING GPS, then there is no difference and you can buy your GPS from anywhere at the best price you can find for a particular unit and they will all work the same.
3) If you buy a MAPPING GPS receiver, then the situation is different. Mapping receivers have a built in "basemap" of local regions (Garmin has six different basemaps for different parts of the world such as USA, Europe, South Pacific, etc.). Basemaps typically include a road map of MAJOR roads and routes in the covered areas. These basemaps MAY also include POINTS OF INTEREST (POI) such as campsites, parks, even restaurants, hospitals, etc. If you buy a mapping GPS <say> from the USA and you live in <say> Europe, then you will have a USA basemap but no basemap for any other part of the world.
4) If provided by a particular GPS vendor, you CAN load detailed maps of YOUR area (within the memory limitations of your GPS) and everything will work fine inside the area where you have maps loaded.
5) With AUTOMATIC DESTINATION ROUTING type GPS receivers, the problems are slightly more complicated. Statement (4) above holds true BUT if you drive out of the area where detailed maps are loaded, guidance will cease or be incorrect. With a PROPER BASEMAP for your region, it is possible to load detailed maps for <say> Berlin, Frankfurt and Paris and then have your GPS (such as Garmin G-V or StreetPilot III) route you automatically from Berlin to Frankfurt and then on to Paris. The units will use high detailed maps inside Berlin, then switch to the basemap and continue routing in the countryside between Berlin and Frankfurt. When Frankfurt is reached, the unit will automatically switch to the detailed Frankfurt maps and then use the detailed Frankfurt maps to route through and around Frankfurt. As you continue your route to Paris, the GPS will switch back to the basemap as you leave Frankfurt and use the basemap until it reaches the Paris high detailed maps you loaded. Then it will switch to the high detailed maps of the Paris area and you can autoroute to your final destination in Paris.
If you DO NOT have a European basemap in your autorouting GPS, you will have to load the high detailed maps from CityNavigator or CitySelect (in the above example) and this will work fine, BUT will require a MUCH larger memory. In the case of the G-V, the 19 megs of memory will be inadequate to permit loading of the Berlin>Frankfurt>Paris trip, but you could probably do it fine in a SP-III with a 128meg memory cartridge. Note: European MetroGuide maps do not have automatic routing details and information for Europe.
Thus, with the proper BASEMAP for your region, you will enjoy much wider operation with much less memory than if you have to use high detailed maps in your entire region.
Where can I buy GPS receivers at a discount?
Try for EUROPE HERE and for the USA HERE
Questions not answered?
Email to Joe Mehaffey Back to Joe and Jack's GPS Information Website