..is hydroscopic--it absorbs water.
If you have a reliable supply of pure gas, even if it is a couple octane points lower, run it.
Your knock sensor will detect the lower octane and pull ignition timing, so no damage will occur. You will only notice the torque drop, if you notice it at all, below 2,000 rpm.
Ethanol is just bad.
Run Shell pure gas if you can, or buy some pails of "T4" from VP Racing Fuel
Here:
https://vpracingfuels.com/product/t4/
I've run this in my Boxster, Ducati Monster with hi-comp pistons, RC51, and GSX1250FA. They love it.
