I have a contour Roam, so may be a bit biased, but, I have been very happy with it, personally I think it’s equal if not better than the go-pro HD, but not as good as the Go- Pro Hd2.
Mounting options on the contour has been a lot better than I expected. I use the the flexi strap, and the two other helmet mounts the fixed and swivel one forget what they are called, but came with the unit. If you haven’t already checked out the contour web site there’s lots of videos taken, search for my screen name and you should find some videos of mountain biking and paragliding, that might give you some idea of quality and stability of the mountings, used in various light conditions.