Ok, let me weigh in.
In my sig I have a 1998 C1500 with 5.7L 3.42 rear end, 4 sp. It has a Jasper transmission and a factory crate engine installed 40k miles ago, total miles is 180k. The TT rig weighs 6500 lbs loaded.
I drive from KY to FL every year and the hills near Manchester, TN can be challenging. I do know the trailer is back there but it tows very nice. I get 8mpg when I drive 65 mph which is the fastest I will go towing. In the hills I you will see me in the right lane and sometimes I drop to 2nd and hold 45-50. My mileage w/o towing is 17. My first leg I am operating about 11 hours or so, by then I am ready to pull over and get rest.
The truck you are looking at is like comparing a tangerine with an orange, so to speak. You will be better off than I am considering the engine will have more HP and you have more gearing.
Someday I will be upgrading the trailer and before that I will have a diesel to pull it. Either way your decision but your decision should be based on how often you tow and how far and how many mountains you intend to climb.
The biggest pain the back with that truck for me is torque, gearing and the need to get gas every 150 miles. With 25 gallons I give myself some room so I do not run out.
Hope this helps.