E85 really isn't catching on at least here in California where I am. Its been running near $4.00 a gallon if not a tad more and most guys that have performance cars use it because of the Higher Octane Value vs. Pump 91 which is the highest we can get here in California.
I used E85 in a Tuned Evo 9 for a while and switched back to 91 pump gas due to a few factors.
1) even though E85 is a "green" fuel the car drank it like an alcoholic at a football game. We are talking about 14 miles per gallon on the Evo or less depending on driving conditions, vs. 19mpg on 91 pump on average. So in the long run the cost savings per gallon, really isn't a cost savings. How green are you if your burning more fuel anyway?
2) Availability, at times I would have to drive 50 miles out of my way just to fill up and forget about taking the car on a road trip since the cruisiing range was so short (evo's suck stock for range anyway but worse with E85) and even though the performance gain was substantial, its not really noticiable unless your really on it and how often are you really "on it" in the street anyway??
So if you happen to have a flex fuel type car and the E85 is substantially cheaper, I am talking like $1.00+ cheaper per gallon, it MIGHT behoove you to use it. Honestly though, the greeen aspect just isn't there, the MPG's arent really there, and here where I am, the cost savings wasn't really there.
Jeff