A split screen would be better, I also want to see the navigation. With the older MS and MS with vertical screens, the camera only occupies half of the screen, something like that would work here, too.
I want to be able to see WHAT/WHO is behind me, not just a tiny wide angle shot that I can hardly tell if it's a car, truck, etc. until it gets on my bumper... It's hard enough to spot the po-po with all their different kinds of cars/suvs/trucks... And their lightbars are only about 4 inches!! But you can't see much at all in the rear view camera... Good for backing up, as it actually makes the view LARGER, but even then, hard to tell WHAT is behind you...