It would take way too long to explain all the negatives such as a few: burn rate, fuel system crystallization, moisture attraction, scored cylinder walls, etc.. Let's just say engines are most happiest without it. For the record, the ONLY gas treatment that will break down completely the fuel system crystals caused by ethanol is Techron. This is free advice with no money back guarantee.
I've tried to explain it in detail to some car loving folks who always come back with the same reply: "I burn too much of it too quickly through my gas tank to make a difference." I have no response for that. That's like saying a little bit of chlorine in my drinking water won't hurt me if I drink a lot more.
Many of the stations around here that are claiming to have deathanol free gas are charging a huge premium for fuel that isn't ethanol free. I've tested all the stations within 50 miles and found only one that was really ethanol free. My wife's new car has had only this fuel in it from new, runs like a top and gets 5-6 mpg better than everyone else is reporting on their similar car. I bring the fuel home in multple 6 gal gas cans to put in the other machines. A pain, but worth every bit.