I drive winding Pennsylvania roads to work everyday which are insanely fun (with there's not someone in front of you doing the speed limit) and I don't take it easy. I have about 2500 miles right now and I average about 15.5mpg. However, this is my first manual transmission car so I'm still getting the nuances of everything, and my mpg is going up as I get better and the car gets broken in. But, as has been said, I didn't buy it for the mileage. Only got 18 in my 4 cylinder I had before the mustang because I drove it hard, so I lost a few mpg, but it's SO much more fun, though I do use premium, so it does add up.
2014 Jeep Grand Cherokee SRT
SOLD -- 2014 Base GT 6 Speed Manual