I'm a low time guy but, frankly, the GPS scares me a little. Not because I don't know how to use it, but because it makes navigation SO EASY that it's tempting to use it as your only source. Like the devil on your shoulder saying follow me, follow me.
The plane I trained in (and now rent) has a GPS and it was never turned on until after I had my license. Since getting my license, the GPS is a powerful force that makes me want slack off in flight planning and situational awareness. I force myself to use VORs, ded reckoning, and landmarks, but that GPS is always on and reassuring me I'm not lost. Having written this, I think I'll leave the GPS off on my next couple of cross countries.