Garmin creates a img file on your sd card, the size of that image is dependent of how many maps you select. The idea is to cram as many maps on a sd card and not to go over the 2011 limit. Some cases I needed a 2 gig card and most of the time a 1 gig was all I needed. The old topo map fitted on 2 sd cards, one east and some middle us, and the other the west and the rest of the middle. The problem came when you tried to overlay road maps with topos, then the came out with topo 2008 which became the best of both worlds. No longer were you limited to trails and service roads, then you picked up everything else. The cost is more sd cards, but after experimenting with it, it ended up a better way to go. It all depends on your mission parameter of what you want to do with it. Your mind will be your only limitation. PM me if you have any specific questions and I'll do my best to help. I always like to see people get the best they can from a product. Garmin makes good stuff, a little pricey at times but still good products.

I concur with KenW the eTrex Legend HCx with a Mapsource loaded with a 2GB micro SD Card will give you the ability to load in 1999 topo maps (Garmins present limit for maps). For me that is most of Western Canada. Its easy to use, has good battery life and the maps not bad. I find when I am teaching people how to use these GPs's they pick up on it easily and can really use the GPS to its full advantage.

"GPS Receivers are an excellent tool for navigation when properly used along side a topographical map and compass."

I'm trying to understand how garmin counts maps. If its not a count of the files on a card then how does it count them. If I were to take the whole US and say drop it on the the card, how does it count, as one, or as one for each state, or is it by the USGS quads?

Eugene, check your PM, I tried to explain how the maps take up the cards a little better.

... thus the reason I bought the pre-loaded microSD with the maps. It is much easier and I have all the maps with me on one card.

That card is easy enough to move over to another GPS when that time comes.

Supposedly Garmin will soon lock down the CD so that it works with only one GPS unit - if they haven't done it already.

In MapSource Canada it counts each 1:50000 Scale Topo Map as 1 Map, in the US I "assume" its 1 1:24,000 maps, but I don't have the US MapSource. These maps only cover a small area so 2000 maps would not allow for all of the continental US.