I use E10 in the Mog and the MG. Occasionally I put a tank of E5 in, but haven't noticed any change in performance or mpg when I have done.

I have used Valvemaster Plus (fuel additive) in the past which reports to remove any of the ethanol nasties, and give some form of octane boost, but again, don't bother anymore.

"Y mae dafad ddu ym mhob praidd"
1972 4/4, 1981 MGBGT, 1984 FLHT1340, 1980 XLH1000, 1990 ZX10