If GoPro's where cheap they would be the bomb. I used to have a Muvi I think it was called, cheap but quality isn't amazing. Contour are supposed to be a great bit of kit. Can't say i've seen the ones you've posted. Cheers
Check out some of the £50 ish Chinese GoPro knock offs in good light they are dead good and cheap enough to confidently mess around with and not worry about.
Woods is right .You can get a sj3500 or sj4000 for next to nothing. They have roughly the same battery life as the expensive gopro cameras .
Reading reviews on YouTube it seems the main thing lacking on cheaper cameras is the switch from light conditions .The cheap cameras take a few seconds to adjust. Otherwise the image quality is similar.