I know people usually get the front protected but has anyone got the doors done? I am thinking it would help prevent door dings.

 

You mean cover the entire door? I don't think that will prevent most door dings, maybe minor ones.
But if some jackass decide to swing his big heavy door towards your door, Xpel isn't going to provide any protection.
I just did my door edges to prevent paint chipping when the kids swing open the door and hit the side of the garage.

I'm not too concern about door dings. I know a really good PDR guy locally here. He does an amazing job removing most door dings on all my cars.

 

Seems to me if you Xpel the door(s) you may be able to protect the paint, but as jdpdata mentioned, you still will get the knucklehead dings, just possibly without disturbing the paint!!! No way to avoid those unless you don't drive.