It does tend to balance out a bit, but in pure highway driving, mine was pulling 40 mpg right off the boat. Now that I've been commuting and going to the store exclusively for a couple months (my commute is 18 miles, 13 of which are highway at 70 mph and the rest in town), I've been getting 35. Actually 35 and some tenths, and over time it's gone slooooowly from 35.5 to 35.1 at the moment. So I can't be happier - that's much better performance in the fuel arena than I expected. I've managed to keep it out of sport mode mossst of the time, but with the exception of a couple test runs, none of that mileage is in green mode either. I do keep the engine stop/start active, though. It's weird, but I'm used to it now.