New Hemi runs extremely well. I had a 2007 Dodge quad cab before. ( I liked that truck as well). 2009 has better acceleration and much nicer ride. I am totally enamored with the whole truck. FYI, mine came with a locking tailgate.
Alpine sound system- It really sounds great. Navigation with bluetooth hands free phone. 4WD Auto on the dial. Comes in great when you are encountering varying road conditions, so you don't have to shift back and forth between 2 and 4 WD. Remote start.
Better fuel economy, can't really complain about that when it has so much power.