I have always wondered about your can under your barrel. I have a Sony HDR-SR12, which may be a bit bigger, but has the advantage of a 120 GB hard drive. Keeping my barrel up is never my problem, it's the problem with my Contour and the Midland's being able to record long files. Seems that if I keep them to no longer than 5 minutes, they tend to film okay, but if I have them for 30 minutes, or an hour, they have a file, but seeing it just does not happen. I am hoping to get a Sony Action cam, and have better luck with it.
But, I have noticed, despite the low definition, that cheap action cam from Jaks Pacific ($50 for the real cheapie, and $100 for the "high end" one) seems to work well with going from bright light to shadow's. Don't care for the mounting options as much, but it might be worth checking out.