If I had the money I would love to get one and it would probably be the Tachyon, because it is relatively still small and is an all-in-one and supports upto a 32gb card (video takes up a lot of space).

Other cameras I've researched are:

GoPro - nice, but did not seem to gain me that much over my regular Canon Powershot.

Several bullet cameras - small, but you need the extra cables and the actual recorder. Did not want to carry around extra stuff.

Plus, to make sure I really wanted to take lot's of video, for now, I made an attachment for my helmet (held on with velcro straps so no mods to helmet) so I can attach my Canon. First big use was today at PDXs Sunday Parkways.

Anyway, if I were to buy on, it would likely be the Tachyon for features and prices.

Good hunting. You can do a google search (videos) on helmet cam and see what others are using and the web quality.