So I was here awhile ago looking at the Avic's and well, Im back....
I have an 06 Sierra Denali. Looking for the Best bang for my buck. Some features I would like to have are ability to have a backup cam, aux out for my ipod, NAV, DVD (not sure if its possible to have both on some models. would rather have NAV if I had to pick), and ability to "hack" and ease of installation of course 
Any ideas would be greatly appreciated!