A Casio "Commando" Android phone with the Backcountry Navigator app is the best gps I've used.
Nice screen, great maps, waterproof, and can integrate with the Delorme inReach for satellite text messaging when you're outside of cell phone range.
I used to have a dedicated Garmin GPS. I lost it, and don't feel the need to replace it, as the Android is just as good, and I pretty much always have my cell phone with me anyway.
Only downside of the Android is that battery life is significantly less than a dedicated GPS. However, I don't keep mine constantly on, but rather I use it for occasional location checks, so that's not an issue for me.