Camera will only see directly behind you, with a lot of blind spots on each side. I put one on my truck and it is only good for seeing what is directly behind. You will still need the eyes of your DW.
Try the one they sell as Sams's club. For $ 59.99 I got the camera, at wireless transmitter and a big 7" screen that can also be used for playing dvds. The camera is wide angle and I can see everything behind me and left & right in other lanes of traffic to about 3' behind the trailer. It is a great deal for the money. They say to hook up the power to the backup lights, but I like mine on while traveling, so I hooked into the running lights as I always run with lights on for safety anyway. I hope this helps. Happy camping