I've got an original Garmin eTrex I bought when they first came out, so figure it's at least 10 years old. It still works just fine, even after living on my snowmobile for most of its life. It doesn't have a high sensitivity receiver or WAAS (or mapping for that matter), so accuracy and satellite acquisition suffers a bit. However, it's still close enough with tracking and waypoints that I've never had an issue finding my way back.

Like most things, electronic items love to "s**t the bed" when you need them most. It's that whole Murphy's law thing. That's why it's always best to have some kind of backup.

Like most people, I rely heavily on GPS units nowadays, but I also still like to take out my map at major trail intersections and take note of where I am and the direction of travel.