Well the project is now complete... the car is back to working order with the latest software and having the DVD changer is kinda fun... in the sense that the kids are distracted in the back seat so I don't have to pull over as often on road trips to change the disc for them!
My advice for anyone considering the rear seat entertainment option - buy yourself a few ipads and some holders for them!
I still can't find the value in having the screens built in, but they were pretty useless to me without the dvd changer upfront for my passenger to change the disc for the younger kids (for older kids that can reach the floor of the car where the rear player is this is not an issue).
At least now with the changer I can make use of the screens! knowing what I know today - I would have NOT got the rear seat screens, and opted for a nice ipad mount that could be removed when not needed and saved some really serious money on this....
either way, there is enough left to buy some more Dinan Stuff!