I am not an expert but do have 2 experiences with BU cameras.
1- I installed a Camecho on our previous TT. Installed it wireless.
pros- less than 100$
better screen image than my current Furion 7" vs 4"
cons- poor reception wireless . I think if It was installed wired it would be fine, although more trouble to install. I ended up installing the wireless transmitter in the front of the TT and it worked great
2- Current GD TT came ready for a Furrion
pros- Easy peasy to install
Wireless works great
cons- Screen is only 4" and hard to see. I think they have a 7" screen version, if so I would definitely buy it
price is way too high, paying for convenience
If my Furrion had a 7" screen I would be really happy with it. I don't really use it much for backing up mainly for observing while driving.
I would not go to the trouble of installing a camera wired. Just too much trouble for me although it should work fine