I think I am able to get more than 300 per tank on the highway...shortly after buying it I drove it to Ohio from Texas, and got as high as 35 mpg across Arkansas. I haven't calculated my day-to-day mileage.

 

I'm averaging between 32 and 37 MPG in back and forth to work driving with my 5-speed xB. I'm not tryin' to drag race any BMWs tho.

 

I don't drive any harder than average either. I have a Injen intake and the Magnaflow Cat-Back and still mileage is dropping. I would think it would be better with the addons rather than worse? I put both of them on immediately after returning from the dealer. So I can't figure out why I am dropping mpg now after 4000 miles of 29mpg?