Not having seen the twenty20 model you posted, I can't say if it is better or worse, all I can do is look at the specs. The newest model Helmet Cam is 560 lines, so I assume it will have better video quality.
The Helmet Cam extreme mount is also a nice option that they offer, which protects the camera and lens from bug strikes.
Both cameras (high end models) look to have similar features and pricing. Here are the differences I found just now.
1. helmetcamera.com doesn't give any specs for their camera other than resolution. Twentry20 gives complete specs.
2. Helmetcamera.com offers extra lenses. Twenty20 appears to offer only one lens.
3. Helmetcamera.com offers a nice remote for lanc camcorders to start/stop the camera and check your camcorder battery and tape status. Twenty20 doesn't offer any sort of remote control or camcorder state indicators. It's either on or off until you can get to the recorder.
4. Helmetcamera.com is tossing in the extreme mount, Twenty20 requires you to buy your own ram mount,e tc.
5. Twenty20 offers a 12 volt regulated power supply with the kit, Helmetcam requires that you buy it separately.
6. Helmetcam's 560 line resolution camera is about the same price as Twenty20's 480 line camera.
An independent reviewer I trust posted a great review of the Helmetcam over on Angel Ride videos. :wink:
Guess which one I'd go with?
P.S. Looks like helmetcam cam out with a miniDVR at a great price. Sadly they are out of stock, it won't work with their remote and even they say the quality is much lower than using a camcorder.