[bamanick]

The wife and I just got back from vacation (took the Sky); I've been very carefult to use nothing but premium fuel with no ethanol content at all. Averaged 25.7 going to the coast and driving there. So the day before we returned filled the tank with regular and 10% ethanol. It increased the mileage to almost 27 for the tank (and yes there was still some in town driving after the fill up).

Hope that helps.