RE: Anyone use GPS?
I've used a Garmin eTrex Legend B&W model for about 5 years. I use it in areas we're not real familiar with for finding the way through back rounds scouting waterfowl in N.D. and pheasants on MN. I'm sure newer models have more memory to download maps. But I can download dozens of maps I need for any give trip. I especially use one hunting Elk out West when we may hike 4-5 miles back in off even dirt roads up and down many ridges and draws. When the Sun is starting to move lower in the sky and we're just starting to head back to the truck, I make sure the GPS is still on and we follow the "bread crumb" trail back out. I always carry extra batteries and a good compass and waterproof map in those places just as a backup. I also bought a retractable lanyard type clipon to the back of the GPS case and onto my belt loop to keep it attached better than just in my coat pocket.
I also used to mark locations that we need to find again (e.g. where we left the field dressed animals over night til we could get horse and mules in the next day to get them out). It's been worth the cost for tht GPS and map CDs for sure.