Just got back from a vacation trip to Maine. Towed our new Coleman E3 to save hotel costs. We averaged around 12 mpg for the trip, which wasn't too bad considering the Pop-up weighs 3k pounds by itself, we had probably 1k pounds of extra stuff with us, and the terrain was far from flat. Got a lot of looks as the Evolution series is not all that common, although we saw two others on the trip and was stopped by another owner with some questions. Truck did good, there was only one place that I could say it struggled; and that was starting from a dead stop on probably a 12% or better grade (it was frickin steep). Keep in mind, its completely stock short fresh fluids and a second battery. I ran cruise control on the interstates, and used T/H in towns and in areas I could use the grade braking. Although the 3.73s do alright, I would definitely never buy another one with anything less than 4.10s. I may even talk with my truck guy (my former diesel guy), and see what he thinks about installing 4.56s and making them work with the rest of the truck.