I can't really understand how there would be turn by turn directions on a trail? This must be a feature for road riding.

17 hours sounds suspect. If I turn the backlight off, I get 10 hours out of the Magellan, but this hasn't been an issue since I use a Shimano Hub and a homemade rectifier set up to run the gps indefinitely.


Little Off topic: but I am using a Magellan with National Geographic State Maps. It's nice to be able to load maps on it and see it on the Detailed topo maps. And when you buy the state you can get the maps updated to yesterday (or something like that)