The screen can be mounted anywhere you want. I believe it is 5" in diameter.
The camera gets mounted where the top license plate screws are.
For power/ground there is a wire harness. The harness plugs into existing ports where your audio cables are located.
Yes, it turns on automatically when you shift into reverse because there is a place to wire it into the rear reverse signal.
Regular aftermarket backup cameras have a long wire that must be threaded from the back of the car where the camera is, to the front of the car where the monitor is. This one is wireless. The transmitter gets mounted in the back, and the receiver gets mounted in the front.
I cannot personally attest to the quality since I never installed this. I did do a bit of research before purchasing it and there were nothing but positive reviews on this model. The camera is purportedly very good with high resolution and lighting. The monitor is color and has a clean crisp image.
Josh