I wouldn't mind running a dashcam but I'd prefer something to just always be running because I don't want to me hiding it away and fiddling to set it up again every single time I drive anywhere and if I don't do it every time then what's the point?
So requirements would be something like:
a) Discreet/OEM type of look so it doesn't look like something to steal
b) No wires hanging about
c) Start up when car starts and shut down automatically
d) Be able to automatically "rotate" files on the sd card, ie record 1,2,3,4,5,6 then when low on space delete the oldest file (1)
e) Quality is important, something gopro like would be great but the go pro's aren't cheap but it would really help to be able to read a numberplate in the video
Then basically it's plug and play and if you do need it for something you just have to pull out the SD card and copy it off. Something automated via wifi would be cool but I think would significantly add to the cost.