I have the iBall.
The lens is so much of a fish eye that it is hard to have any depth perception over a distance. That said it
will work all the way to the back of the camper. I use a tractor to move my TT from it's hangar to the staging point, and then through the gate to the driveway where I hook up the truck. There are a few spots where I have less than a foot to play with and I use the iBall to help me stay out of trouble. I've installed a cigarette lighter outlet on the tractor for it. (Should have seen the faces at NAPA when I explained that one...
) For hooking up the hitch it is absolutely awesome.
The 9 volt battery in the camera needs to be very fresh, or the picture quality deteriorates quickly. Also, it appears the thing does it's business on the same band as the bluetooth connection in my truck so especially when I fire up the truck and my iPhone and the truck "shake hands" there's a lot of interference. I can either wait 'till they are done, or turn off the bluetooth in my phone.
For the money I really like the thing.