I have had a 480 and a 580 (both in NTSC which has a higher count than PAL) While the 580 gets much better video it is more due to it user the newer Sony chip (ExView Super HAD) The newer chip adjusts to light faster and has better color.

Also be aware that there is a v1.5 and v1.6 on LANC switches. The older Sony and Canon cams use v1.5 as you turn the switch to VCR mode and use the LANC for on/off record/stop. The newer Sony has a rocker switch, the first time starts the cam in video mode. You then rock the switch twice to set it into VCR mode. LANC v1.5 will control record/stop and even turn the cam off but will turn the cam on in the incorrect mode. LANC v1.6 starts the cam into VCR mode directly and allows the normal controls.

I use my mounted to my helmet with the cam in my backpack for street riding (skiing and snowmobiling also) However on the track I put the cam in the tail of the bike as I do not want any distraction (or loose wires)

DISCLAIMER: the affore statements pertain to US cams and may vary on European cams.

Hope this is some help.