Great truck for the ride & comfort. The 6.6 Diesel has exhaust re-gen problems, GM says there is no fix, get used to the smell of exhaust in the cab. I would not recommend the $8,000 for the diesel, go with the 6.0 gas engine. I get 7-8 MPG pulling a 34' 5th wheel...lots of power, lots of exhaust fumes to contend with. The Allison trans is a great feature!
The Allison trans with 360 hp in front of it. Can pass everything on the road except a gas station.
Work on the exhaust problems. Then they'll have the best truck on the road. Rear air would be nice for the rear passengers.
Chevy has done a great job of combining comfort and usable power into one vehicle. I use my 3500 to tow a 35 foot fiver through mountain areas with no problems. the Allison tranny is great for hauls done or up long grades.
By far my favorite feature is the Allison Transmission.
The interior storage is pretty limited if you spend a lot of road travel time and have maps, guidebooks, etc.