hi richie :thumbup
it was what i wanted to use, but had the slight wiring issue (my fault, nothing to do with the archos). i was filming using a cheap SD card based camcorder that i got from aldi for about £100. that is brilliant in that it records in HD, but is not really small so cannot be attached to side fairings etc like a bullet cam can. wind noise is a problem too. i'm buying a spare seat cowl to use to mountthat to for rear facing footage, and will have the bulletcam for forward facing.
i bought my archos 405 used from ebay for about £60 and each half hour of footage uses about 0.5GB of storage
you need the official 12v to 5v power supply though, as it is capable of supplying the 2A that it consumes when connected with the camera.
looking on the archos site, and on amazon, it would seem that they are no longer selling the helmet cam
the video footage of me was taken from an oregon scientific ATC3K which is good as it's small, light, can be attached anywhere, records to SD card etc but the quality is not as good as a bullet cam, especially in low light