I bought an 'action cam' that has a dashcam function. It also has a Sony sensor and pretty good picture quality day and night. The only dubious thing about it is the name - Git 2.   I also bought a nextbase hardwire kit from maplin.   The camera and holder   I was going to get a dedicated dashcam but it seemed a bit of a waste. With this I have a fun little toy that can go in its clear plastic case and be taken under water - drive to the airport car park then take the camera with me. I