I have a friend that's an outboard motor machanic. He says E85 is the best thing that ever happened for his business. The Marine grade Sta-bil seems to work well if you have to leave it sitting for extended periods. I have mad it a habit to add it to every gallon I purchase that's not going into my vehicles. So far, no problems.
I was expecting something similar when I had my fuel pump apart yesterday, but it looked great inside. I have had issues with rubber fuel lines already, and at only 2 yrs. old I've already replaced some lines that were unusually soft.