They're great little cameras. I use mine on the dirt bikes, not on the jeep so much. If you're going to get it for use in the jeep then definately get it setup with 12v power or get a spare battery. Make sure you use the open back case because the full waterproof case doesn't let much sound in. I have the rollbar attachments, mostly for attaching to dirt bike frames but they can be good for bullbars, jeep rollbars etc. Change the view/angles often, it makes it more interesting!
Here's some videos of mine filmed entirely with the GoPro. This one was me holding my helmet with the GoPro attached filming me and the boys out practicing and towards the end there's some footage of me riding my bike with the cam attached to my helmet:
http://youtu.be/yRkeD8EhEH0
This one i tried a few different positions while at a competition. Kinda looks funny but makes it interesting. Fast forward to 4:00 minutes to get a good idea of what i mean, there's some more multiple angles at about 6:00 minutes:
http://youtu.be/CefMUDb0GaU
cheers