Well we brought it home yesterday and I could really tell a big difference just on the short ride home. MUCH more pull from a dead stop. I can't wait to hook up the TH this weekend.
Coming home I couldn't help but feel like it needed to shift up, that'll take some getting use to. I'd guess about 500 rpm at 60 mph difference. I'd say empty mileage could take as much as a 5 mpg hit, but that's OK.
Something else too, coming from my 2500 to this I swear there's hardly any noticeable difference in the ride quality either, and I noticed ALL 6 tires were over 80 psi coming home.