First I have to say that you got an incredible price on that package. That is a very good unit for the money.

You shouldn't have much trouble watching DVDs on the Kenwood HU. All you have to do is run a switch for the eBrake wire. If the system thinks you have your brake up then you will be able to watch whatever you want. The problem with the Pioneer is the software. It senses the car moving with the GPS tracking. Even if you have your eBrake "UP" the system will still know that the vehicle is in motion. The only input that you can watch is the rear camera. That is the reason for having to "Trick" the system.