I have had one Garmin previously. I looked at the CW/Rand McNally RV GPS and while it was able to use WiFi, I didn't like how it was mounted to the window mount. I then bought the Garmin RV760LMT and like it very much.
It is NOT perfect... I just returned from a 15k trip to Alaska and back. I used it 99.9% of the time. I had four incidents that the Garmin took me on gravel roads that were maybe 9 feet wide! Or, tried to send me backwards after taking a lunch break.
I noted the four incidents and will send them to Garmin and hopefully they'll include the correct routing in a future update.
Over all I like the unit and how it is mounted to the windshield mount. I can remove and reinstall it with one hand. I found that if I entered the city the CG was in before putting in the CG name, the results were faster and more accurate. It has a LOT of CG's, BUT there are a lot of quality ones it doesn't.
The one problem I have, depending on the sun angle while I'm driving, there are times that the glare off the dashboard on the screen makes it impossible to see the screen accurately, and I do have a sunshade that helps most of the time.
As for backup cameras, I went with a Tadi Brothers hardwired camera above the license plate of the SUV (a tremendous help when aligning my hook up to my ProPride hitch, or when trying to parallel park with the stinger sticking out when I without TT) and the a camera mounted high on the back of my TT. I leave it on when traveling and can see the traffic behind me. Both have great night vision. The one problem I have is when traveling in a rain or mist, the camera will get covered with spray due to the way the wind and rain swirl over and around the TT.