You get 60% more wheel torque in first gear. You'll notice it when towing!

If you like your current truck, you'll love the new one! You'll have far more power accelerating, cruise in 5th gear at 2200rpm towing with seldom downshift to 4th and 3000rpm. Unloaded I have had as high as 17.7mpg hand calc over 1000 mile trip in our SUV form with cargo carrier on hitch and Rocketbox on top. 40k miles on ours in 27 months. And you'll love the larger fuel tank!
Does either truck have the 4.10 axle? GM rates the towing at significantly higher for the 4.10 over 3.73, far beyond the 10% gearing for GCWR. My personal opinion is that the 3.73 is underrated and 4.10 appropriate. Many people think the 9500ish pound tow rating of the HD is low when comparing to current half ton.s We both know that is half the story, but it is what it is.