Good idea, removes a requirement for Video cable wiring, but how will you power it? Still need to route power, tapped into some electrical source?
I did it the long (proper) way with leads. It was very difficult getting the Camera wiring to route via the same grommet in the tailgate, that the factory wiring uses, from the car! But worth it in the end.

Also for reference, the rear camera you'd want it positioned along the top of the rear window somewhere - because at the bottom, once that Spoiler opens up, you'll lose alot of visibility (on a Coupe)!
Edit: Another better option perhaps, one of those rear cameras integrated into the rear license plate holder. That way you get clear visibility FROM the back of the car (rather than the view from inside).