When I was looking for a helmetcam I did quite a bit of reading around and weighed up stuff like value for money, video quality, form factor etc. In the end I went with the Drift Ghost S, that I got from RoadcraftNottingham. Have a look at some of my youtube vids (DukeNinja). I alternated from top mount to side mount to held just by the pilion strap.

https://www.youtube.com/channel/UCHi...Wrcx-8A/videos