Just got done doing 350 miles up and back to N.H. Temperature was 95 degrees. Up and down all the mountains, A.C. set to 72. Cruise set to 70 to destination and 75 from destination. Downshifted to 5th many times. Got 27 M.P.G.! Very pleased. With no A.C., might have touched 30 M.P.G. 70 was around 1700 R.P.M., 75 was around 1900 R.P.M. I think the ECO-BOOST works harder, which it should, therefore you may not reach that 30 M.P.G. everyone is seeking. We have 4200 miles on this 3.5 SEL FWD and enjoy it very much. I feel FORD is making a mistake going to strictly 4 cyl. motors starting next year. M.P.G. is not the 'end all, be all'. Thanks.