I was looking at adding a new head unit but i would like to keep the rear entertainment usable. I am not finding much luck in finding out if i can use a reciever and just download movies to a usb stick or if i would be better off buying a reciever with dvd compatibility.
any of the newer pioneer or kenwood decks that are not bottom of the line will do it, many of them will support dual zone/rse with the right adapters
and many brand name decks are compatible with the maestro RR which is a programmable interface that lets you retain most or all of the built in oem radio features and Bose if you have it.
if your thinking of a chinese android deck they will not support rse nor dual zone, at least none that I have seen will.