Local station here sells this stuff for sometimes as much as 80 cents less a gallon. I have a 97 grand Marquis had about 70k miles on it so I put one of those conversion kits on there as an experiment. Really wasn't concerned about long term consequences as the car will likely rust out before the engine is an issue. Car has 91k on it now.
Some observations. The car runs far smoother on E85 with better acceleration and no ping as it sometimes does under regular gas. First oil change was filthy, but now when you approach the oil change the oil is still see through and has nowhere near the volatile smell, it smells for the most part like oil out of the bottle. This substantially cleaned out the engine, a before and after peek under the valve cover was nothing short of amazing. Pulled the intake manifold and all the intake ports look much cleaner.
Downsides, you get more steam out the exhaust, which undoubtedly will be bad for the exhaust long term if you don't get up to operating temp. Fuel economy suffers, in the big car the difference was not much, not enough to offset the savings at the local prices, but could swing things the other way if the price spread is poor.
Some observations. The car runs far smoother on E85 with better acceleration and no ping as it sometimes does under regular gas. First oil change was filthy, but now when you approach the oil change the oil is still see through and has nowhere near the volatile smell, it smells for the most part like oil out of the bottle. This substantially cleaned out the engine, a before and after peek under the valve cover was nothing short of amazing. Pulled the intake manifold and all the intake ports look much cleaner.
Downsides, you get more steam out the exhaust, which undoubtedly will be bad for the exhaust long term if you don't get up to operating temp. Fuel economy suffers, in the big car the difference was not much, not enough to offset the savings at the local prices, but could swing things the other way if the price spread is poor.