The suspension and brake upgrades made in 2011 are responsible for a much improved towing experience over the older trucks. The upgrade is absolutely noticeable and in my view worth the upgrade. The 6.0 while not specing as well is still competitive with the other two going up the hill. The 6.0 with the 6 speed is a nice combo. I have had two of them and pulled the heck out of them. They are rock solid. The 2020 HD trucks may provide something better of course but the current 6.0 doesn't give up enough to either of the other two to matter from a performance stand point.