F150. I wouldnt be too concerned with 5.0 vs Ecoboost either. The mileage tends to be very similar.
GM and Dodge both took bailout money, Toyota frames flex like mad (there are videos, it is bad) and the Nissan Titan is an 8 year old design and gets lousy mileage. That leaves Ford.
I went through this debate last year, bought a leftover 2011 in February and have not looked back (had a 2005 Nissan Frontier and while it was a decent truck, the Ford destroys it in every way and gets the same mileage).