On another board someone made reference to gas in different areas of the country getting better or worse mileage. I think the general reference was that the formulation in heavily populated areas to reduce pollution actually gave worse gas mileage. The reason I ask is that I live in Atlanta and have only been getting 15-17 MPG in "city" driving. Needless to say, that is a disappointment. Does anyone have any knowledge of gas variation affecting mileage? I am aware of the special mixes for different regions or cities, but I thought that was solely for emissions.