Mileage isn't as good running E85. It may be higher octane, which is good for high compression engines, but it doesn't have as much energy. You have to burn more of it to make the extra power. Daily driving a normal car, you get worse mileage. That being said, your cost is about the same as regular unleaded, because a tank of E85 is a bit cheaper. The government subsidizes the ethanol a bit to encourage its use. However, current ethanol production isn't great as far as net energy production. Think about all the fossil fuels used to produce it. Diesel for farm equipment to till, plant, and harvest fields. Transportation by semi and rail car to storage facilities and refinement facilities. Electricity mostly from coal burning power plants used by equipment in the refining process. Then you have to mix it with gasoline and transport it by semi again, this time to a gas station. There's a lot of energy that goes into E85 production. However, the purchase of it does support the industry, which is trying to develop more efficient and sustainable refinement processes, so I guess that's a good thing.
I haven't read this whole thread, so I don't know if this point has already been made.
