@ard - properly installed, with the right equipment, you have constant recording, including a parking mode.

I guess it all depends on where you drive - in my 20 years of heavy driving (with a few years of commercial), in 3 different countries (places I've lived full time and drove on daily basis for more than a few months), I've had hundreds of situations where if not for myself, then at least for someone else, a camera would have been a very credible witness.

You are looking at $100 for a VERY decent piece of kit.