I drive a 2010 Ford Escape 6 cylinder with FlexFuel capability. When I use gasoline I get 28 mpg on average on the highway and 25 mpg for mixed city and highway driving. I tried burning E85 and my mileage dropped dramatically. On my third tank I was getting a little over 15 mpg. I am back to burning gasoline. If you factor in the pollution caused by growing, harvesting and processing E85 I doubt that it causes less pollution than gasoline. As for performance, my car was more responsive on E85.