I have a 2011 F150 with the Ecoboost engine in Regina. I've had it since I purchased it new in May, 2011. It's a crew cab 4-wheel drive with a 3.55 rear-axle.
The best I've ever done was a summer trip to Candle Lake and back (950kms) hauling air - 11.8 litres/100 kilometres. Typically, I do between 12.5-13.5 litres/100 kilometres on the highway with my wife, two girls and all their "stuff" in the box. That's driving 120kms/hr (sorry, I don't know what that equates to in mpg). I typically do a bit better than my brother-in-law- who has my truck, but a 2010 with the 5.4.
In the winter, driving mostly city is between 16-17 litres/100 kilometres.
I don't use my truck for business, but the power (torque) is intoxicating and its all available below 2,500 rpm. My dad has towed a 22 foot enclosed trailer back from the U.S. full of building supplies and he said it tows like a dream. I don't mean to start anything here, but my truck is way "tighter" than how I remember my old 2004 Chev Silverado (which I only kept for 20,000kms from new).....fewer squeaks and rattles and just overall a better truck.
If you're buying an Ecoboost for great mileage, you'll be disappointed. In my opinion, it's the best overall truck out there.