If you are going to bother with one mate - get one that's 1080p recording - otherwise you'll hardly be able to see the reg plate.
If the sensor isn't good (i.e. £23) you'll also see nothing at night.
I'll give you one for much cheapness
Used one while test driving the California T yesterday - got invited so went to brighten up my day and record some interesting footage - one thing worth remembering is that GPS enabled means it shows speed. Mine will have to be edited out for public viewing
