Sandy and Shirley,
I saw that unit being installed at Marlin Ingram RV in Montgomery, AL. I did not stay around to see if they got it working. In AL you do not need toad brakes if your vehicle is under 3,000 # so I have not installed. Frankly, towing the Focus is like there is nothing back there. Hopefully other states will reciprocate. We did have quite a time getting all the lights to work.
I had Ingram install the battery cutoff to the right of the battery on the negative cable. Works just fine. You are right on the electronics except my Bluetooth and clock maintain their settings. The biggest problem is that it seems to lose all the computer driving instruction. You then will have those annoying double clutch jerks until it resets.
All in all I am very happy with this toad. It is fun to drive and has a lot of room inside (once I stuff my large frame into the seat!).
Ron