I bought the matthews mastermount car rig and gave it a full day of test drives yesterday. Its a very clever system but the short story is that I was not able to get stable footage from my 7d with it.

I have hopes for ways to modify it to work, as it got very close, but out of the box it didn't really get there.

I posted some photos and a lot more yammering on the subject on my blog if anyone is interested.

cheers!

RigJob: The dusty broom closet of indy film production.: Matthews Mastermount Car mounting kit (http://rigjob.blogspot.co.nz/2013/02/matthews-mastermount-car-mounting-kit.html)

Nice review. Those are serious looking suction pads. I think you could support a human camera operator with a few modifications, but I don't like to think how the lower support would attach to said human!