I use the Topo maps in my e-trex Legend. It's great. I really like being able to record the track while trailriding in a new place then transferring the track to the home computer for detailed inspection later. I've even taken the laptop along for the ride and used the topo maps with GPS feed to keep track of where I was. A big screen plotter. Most roads are on the maps right down to disused logging roads. I've noticed some of the road information is a little out of date but most roads pretty much stay put. You can load only the maps of the area where you'll be so you don't use too much of your memory. With a little creative file juggling you can load the whole of the disks onto a computer so you don't need the disks to use it. They should have made that an easy option but I guess it would make it too easy to share the program with all your buddies. (Back up copies of the disks work fine) My only problem with it is having to remember to take my reading glasses with me so I can make out all the detail available on the maps when using the GPS by itself. Every little ditch and gully is on there and most are named. Only the main roads are named however. Overall, I'd recommend it if you don't mind the price.