My brother in law and his son have both the 5.0 and Eco Boost.  He told me the other day that on a recent trip where they had both pickups on the road that the fuel mileage was almost identical and he said that it appeared the 5.0 would out gun the ecoboost in a drag race.  I do think that the ecoboost will outpull the 5.0 because of the good torque curve.  But that is probably the only place it will out perform the 5.0.  The way the checked the fuel mileage was they both started out full and drove the same roads and filled up at the same place.  The 5.0 is owned by the son and I would imagine he may have been a little harder on acceleration as he is a teenager.  I thought a direct comparison like that was very helpful. Ford has done a tremendous sales job with the ecoboost convincing people to spend extra money for an unproven engine.