I bought a wireless system from Rear View Safety Products. Installation went fairly well, but I did end up mounting an antenna (supplied free by RVSP) on the side of the trailer to improve the signal. The monitor is great, and the ability to add up to three more cameras is nice, although I can only see me adding one more to help with hitching up. The wireless system does suffer from interferance at times, but overall, I'm pleased with the system and didn't want to deal with a wired system.
Customer support from Rear View Safety has been very good. They respond to emails very quickly and you can also contact them via phone.
2012 Newmar Bay Star 3302
Blue Ox Avail
BrakeBuddy Advantage
2015 Malibu
"Get busy living, or get busy dying."
Andy Dufresne, The Shawshank Redemption