Not only equipment differences but highway vs local. As a rule my weekly mileage back and forth to work sucks and I am below 275, it's all local and I do enjoy the occaisional quick start off the line. I could maybe squeeze more out but don't want to take any chances. Pure highway driving gives me around 22 - 23 MPG even at speeds exceeding 80 for long distances and in that case I am around 350 per tank. Let's face it nobody buys these cars for fuel economy.