Ok I have had a d3 for 2 years now and I would like a f900 but can you us the nav and have a dvd on at the same time? The only thing I use is the dvd/cd nav & radio on my d3 so as long as that all will work I will get one

PS. I tryed to search it but did not find any thing

Yes it will work but obviously you cannot see both screens at once. You will also need the bypass performed. You can switch between screens easily or just listen to the DVD audio while the map is displayed.