Hey....It's likely that you'll replace the crappy stereo anyway so get a head unit that does it all and has the option to connect a back up camera. My camera gives a wide-angle view so backing out of a parking space affords me a better rear view that I could get by simply turning and looking behind. Makes sense as the camera in located just above the plate whereas I'm seated 5 ft forward from the camera lens. I love it for those instances when ya have a massive SUV or truck blocking the view.
My 2 cents
Steve