We had a 5.3 Chevy and purchased a 2012 Ford EB with max tow and HD pkg. We LOVE it and we have read about others having a problem with the misfire. We had a problem, don't know if that was what it was, but took it to the dealer upon returning from a trip when the truck would kinda sputter when we were taking off from a stop. It took them about 3 minutes to reprogram and we have never had another problem with it.
As far as I'm concerned, I had much more problems out of my Chevy than I have had with my Ford and will continue to stick with them. There are so many problems with ALL the makes of vehicles now that I feel if you have a good dealer, you should just stick with them.
I get right at 20 mpg not towing and right at 10 mpg if we are towing and we tow to almost our max capacity. We have also towed a 1500 lb U-Haul trailer and got 10 mpg!! I don't think it matters what it weighs, just that something else is back there. We have plenty of payload and lots of power.
Don't rule out the Ford just because of that one problem, there are lots more of us that have had great success with them.