I have a Drift HD and a VIO POV.HD....I find myself using the Drift more, it has a lot of mounting options with the lens being able to rotate over 180 degrees. I like that it has a wireless remote, and a screen to ensure your mounting position is getting the right field of view. gopro has no viewing screen but can be purchased separately, and has a waterproof housing that seals the camera and works great underwater. gopro mounts are suspect tho, seen a few lost going thru low trees and from crashes. they really seem to stick out a lot, especially mounted on top of a helmet.
I just bought a Contour HD 1080 from backcountry.com or Steep and Cheap .com for $137.99. Haven't used it yet so I can't comment on the quality of video. But the price was certainly right.
Was looking at the original science ATC9K from Costco in store. the videos on you tube they look good but was talking to launch cams he said there not vary good...