I've been getting a constant 27 to 30 MPG since I got my MSP. 3300 miles on it now. I put about 80 miles a day on it, to and from work, 50% freeway, 50% stop & go.
I have noticed one thing. My MPG is directly related to the brand of gas I'm running at the time. In my area, I've tried Shell, Exxon, Conoco & Chevron. I get the best mileage with Chevron Premium. (93 octane) & Conoco Premium. The car runs like absolute CRAP on Shell Premium and the others are hit/miss.
Unfortunately, Chevron is the most expensive. :/