I'm jaded because I too have an '06, but the neat thing about it is that it is the only year with the 3.5 liter, and even though the newer models have a slightly bigger bore diameter, there is something nostalgic about having the first model year of a vehicle.
Besides, the adventure package itself is what makes the truck so awsome. If you can't find an '08 that has it, you will have to build an '09. Say goddbye to the great price.