If MPG were the most
important thing, I wouldn't have a full size, or more likely, any truck. Having said that, I want a truck for the abilities of a truck, but can't say MPG is not still a factor. Once decided on the truck, I want a truck with innovative engineering in it, and from a company that "stands on its own 2 feet". I also could have gone with the 3.7L if MPG was my next level of concern, because it beats the other engines on that, but at the expense of some capability.
I was after a turbo Diesel F150. I waited for years for Ford to come out with a Diesel F150. In 2010 they almost did bring the 4.4L turbo Diesel to market. What I wanted was the Diesel Torque and the mileage. the Diesel didn't come, and the Ecoboost came the closest to the mark. The Diesel would likely have been more fuel efficient over more operating range than the Ecoboost, but the price of Gasoline vs Diesel killed it (in the US, 4.4L is now in the Range Rovers in Europe).
I'm not complaining about the MPG of the Ecoboost. It is certainly capable of the EPA estimate, but I still believe it could be capable of better, likely with some mods to free up wasted or bottle-necked energy and maybe a tune. (ok, bring on the warranty disclaimers and warnings
Some subjects can turn into heated arguments around here for some reason, but I don't see why one would argue with having the best of both MPG during unloaded daily driving and Torque/Power (and reasonable MPG) for towing/hauling.