I just traded in my C6 corvette for a 2014 Terrain SLT2 and when i was at the dealer the sales guy kept trying to get me to buy a Denali for an extra $4,000 it didn't have the rear dvd entertainment system but I couldn't really see any other differences other than Cosmetic stuff like Grill, Tail lights and color rockers? Is there something I am missing I tried to compare them on GMC.Com but it would compare the Denali to the other Trims?