I've got the ContourHD (720 version, not the 1080P out now). It's light weight, seems to work well, I've got it on my helmet and use it everytime I ride.
Pros: Relatively inexpensive (the 1080 is much more $), takes fair quality video, has decent support from the manufacturer, is fairly easy to use. Takes up to 16G MicroSD cards. Laser aiming for both direction and level, can be done with the camera fully mounted and ready to go.
Cons: Not waterproof at all despite claims to the contrary, so you need to buy a $40 waterproof case if you plan to ride in rain. Stick-on pad mount won't stay stuck to any curved surface such as a helmet; it will slowly peel off. I was lucky, I found my camera under the counter in my kitchen where it had fallen off overnight. I ended up pop-riveting the mount to the helmet. Low-light performance is definitely lackluster. No remote mic jack or ability, so lots of wind noise if not mounted behind a windscreen. Beeps to indicate on/off/recording status aren't loud enough to hear over the wind when you're moving. No external power ability;can't record while charging. Records into an oddball MOV variant that editing packages like Vegas Studio has problems with, typically loosing sound or sound synch. Can't disable auto power off after 10-15 minutes of non-recording time.
Now, don't take all the cons to indicated I dislike the camera; these are for the most part relatively minor issues except for the adhesive pad problem, that was almost an LOC event. Most of these cons relate to how I use the camera, which is to record every moment I'm riding and not just specific events or activities. For the $169 I paid through amazon it's a good camera, though having to pony up an extra $40 for the waterproof case was disappointing.
What I really want is a Clubman Pro4 from Stack Electronics, but that's two grand so it's out of my pricerange.
