i use a 60csx. runs on 2 AA batteries. never had reception issues in heavy trees. fairly tough unit as well. i have this on my motorcycle when i go play in the woods. right now i have mine loaded with maps from the open street map project, and the nwtrails project. i have city navigator, but openstreet map is free and community maintained, so there may or may not be more detail in some areas. i upgraded mine a 2GB card, so plenty of storage space as well.