Pros:
- Full boost a few hundred rpm earlier
- 40-50rwkw more top end and midrange at the same psi
- Response of small turbos with power of big
- Smells awesome
- Engine idles smoother, feels smoother
- Better/safer fuel for the engine
- Car is basically set up for it / will only need a retune, ~$500
- Plenty of United E85 servos around these days, costs about the same as running premium 98
- No soot over the back of car when running a rich tune or catless setup
- Once you've had E85 you won't want to go back
- No one who's used E85 has anything bad to say about it
Cons:
- Potential loss of licence
- Wanna make sure there's a couple E85 servos near places you frequent
- With Power FC have to run E85 tune full time unless you have a laptop and data cable that you can switch the tune out with - I do this fairly regularly for long distance driving and it takes all of a minute to do
- Nothing else, E85 is the best performance upgrade you can make