The whole idea behind having a diesel is that you get reasonable gas mileage while towing things. My old truck was a 1999 CTD 5.9 and I loved the motor. It towed things, got good gas mileage,"up to 23 mpg unloaded", it was very reliable, and I still got 16 while towing my boat or trailer. The 6.7 gets more like 15 mpg on average and drops to about 8-10 mpg when hauling things. What that means is that I cannot afford to drive this truck. I think that Dodge must have been associating a little too closely with the environmentalists. The old Cummins motor was an incredible piece of engineering, this new motor with it's clogged up exhaust and EGR junk is just a piece.
New 6 speed transmission is great.
Go back to the 2005 5.9 liter motor. The reason I gave it a "2" on fun to drive is that it is not fun to put gas in this truck at the rate that it consumes it.