We new RV owners just installed a wireless backup camera ourselves! We went with the Rear View Safety model RVS-7706123WQ. It has a great signal standing still and has a good picture, but we haven't tried it yet while moving.
Major problem: There was absolutely no resource whatsoever that walked us through the installation process; not from the company, and not from the web. We found one youtube video that gave us a very good idea of what to do, but without the details. The people from Rear View have been great to work with, and their shipping was immediate, but they do not offer camera installation how-to's.
In the end, we had to research how to tap into wires, what size butt connector to use, how to read a multimeter, what the best caulk is for screw holes in fiberglass, how to drill fiberglass...and so on. For us, it was a husband/wife project that ended with a huge sense of accomplishment!
Although there was a lot of pre-work involved, the actual installation process was pretty easy. Hopefully we will feel safer, knowing that we can see what's going on behind us at all times. In the picture, ignore the few pieces of electrical tape stuck to the ladder that we put there temporarily while we were working...LOL.
Here's the finished product: