I run a flex sensor on my stock P01 ECU.
I run a big spin on fuel filter, switch to straight e10 87 el cheapo pump gas in the winter storage.
I'm convinced he 'goo' people tend to get in their fuel systems from their cars sitting when running E85 is due to water getting in the tank. If you have a good, sealed tank where air isn't allowed to get in and out, park in a consistent temperature space or something cooler, you stand a much better chance.
e85 absorbs moisture from the air. If your fuel tank is exposed to the air and you live in a place that is very humid and gets lots of temperature swings where there is condensation, that condensation is going to end up in the fuel tank and combine with the ethanol and goo stuff up.