Interesting that you would bump this thread now.

A local gas station opened up about 6 months ago and started selling 100% gasoline. I haven't seen "real" gas for over 10 years! All gasoline in this area is E10 (10% alcohol/90% gasoline).

For the last few tanks I have been running 100% gasoline in my Mirage as a test to see if I notice any MPG difference. So far it looks like 100% gasoline is good for close to a 5% increase in fuel economy over E10. The testing continues and I will write something up once I have enough data. If this is the case, the MPG hit you would take by running E85 in a Mirage would be significant.