covetsthesun,
The truck rides very smooth and the seats are very comfortable. It's so quiet it takes some getting used to. These trucks really are more like luxury cars. I have only driven it about 30-40 minutes from home so far so no long term seat time. It is 4WD with the auto transfer case option. Just select what you want. So far I haven't used anything other than 2WD.
I went with the 5.3L for the fuel economy considering it has slightly more horsepower and torque than the 6.0L that was in my 2005. I anticipate being just as satisfied with the towing ability. Payload according to the door sticker is 1,614 pounds and towing is 9,600 pounds. Both are an increase from the previous truck.