E85 is hard on older fuel system rubber parts and seals not able to tolerate the solvent properties.
It also has a much greater water absorption issue. When phase separation takes place you are in a world of hurt.
So lets step back and take a look at the results. E85 is:
-at best, the same price as regular gas but is usually more expensive.
-severely poorer fuel mileage. Stopping more frequently also reduces economy.
-doesn't store well.
-has a higher risk of water absorption which causes damage to even flex fuel the systems.
-more corrosive to older fuel systems.
-has created a drain of corn supplies with increases food costs (corn for beef, corn for sweeteners which go in a ton of food and drink products, etc).
What a great deal.