I have a 13 Platinum Ecoboost 4x4 Max Tow. The MPG is pretty poor. I love the truck, love the turbo power, it's as close to a diesel as you can get with Gas. If I were looking for something to get better mileage, I'd probably get the Chevy / GMC with the 6.2L or the Ram with the 5.7 L both with the middle axle ratio. Reason being the cylinder deactivation I think results in better real life MPG than the smaller engines because they can operate at higher MPH speeds than the smaller engines can stay out of boost. I also had the dreaded "loss of power" due to condensation issue. Happened 2 times to me in the first month I had it. It hasn't happened since, I have 19K miles on it now (bought new).
My Max tow is in the boost constantly over 70MPH and as a result the MPG go from about 19 at 65 to 18 at 70 to 16.5 at 75. That being said, there is always power and you can tow at any insane speed you want on pretty much any incline.
The bigger V-8's with cylinder deactivation can run in 4cyl mode longer than the smaller (5.3) can due to more HP in 4 cyl mode. It's counter intuitive, and I bet the EPA doesn't agree, but I just think that's the real life result.
If I could do it again, I'd get the 3.5 L with a 3.55 Axle ratio TOPS, maybe even 3.23 or whatever ford offers in that range.
The 2015's looks very interesting! The 700lbs savings will help big time with city mileage, I just don't think Ford has the answer with the small turbos for real life mileage. They may lead with sticker MPG, but if mine is evidence, they don't match reality.
Again, love the truck! Just not the MPG.