I've only tried a two sided tape helmet mount near the lowest point of the windshield, and the video is so distorted from vibration that it's basically worthless.
I tried various positions using the suction mount - http://www.youtube.com/watch?v=u255mFMpP3E
But the shakey engine makes it quite fuzzy, though it does look cool in the various positions.
Overall I really like the chest mount - http://www.youtube.com/watch?v=jMJYNjkoxFk
I've only tried a two sided tape helmet mount near the lowest point of the windshield, and the video is so distorted from vibration that it's basically worthless.
Here is a brief video comparing the suction cup tank mount, top of the helmet and chest harness. Shot from my '99 S3. Personally, I prefer the chest mount.
http://www.youtube.com/watch?v=w8Idv...ature=youtu.be