Back up camera for truck and even on a fifth wheel??

I went with Rear View Safety. They have a monitor that attaches to the rear view mirror on the windshield, and I can select one of three inputs (I use only two) I have a camera on the tailgate, and a camera on the rear of the fiver. When I'm not towing, I use the tailgate camera. When I'm towing, I switch between the two, as I get a great view of all four of the fiver tires with the tailgate camera. Full wired system cost about $300.