[D13]

e85 has roughly 15-20% less fuel value. So unless you get it 20% lower in price it's not 'cheaper'. It requires more fuel in the ratio so your consumption goes up and MPG goes down, given an engine not specifically optimized for e85.
It burns slightly cleaner (less polluting).
The big plus is its resistance to detonation. A small displacmeent high compression eninge on e85 can make as much power as a larger engine on regular. For engines over 9.5:1, it is a cheap alternative to premium plus additives or race gas. For a DD, a small turbo'd engine can take advantage of its anti-knock properties.
Most fuel line made in the last 10 years is e85 compatible. Most gas is already e10.
Corrosion is a risk mostly due to sitting, where the fuel will attract water.

Nice to know QuickFuel does smaller carbs too. Eventually going to go e85 on my 250, and that will be an important part of the equation.