Well I'm now using Esso synergy 99+ as although it's marked as E5 at the pump (has to be by law) Esso guarantee its ethanol free in most of the UK. However after my little issue with my Makita I'm now adding a little redex fuel cleaner (only needs about 1.5/1000). That's on top of a similar amount of star-tron fuel stabiliser....I may be over thinking all this! The alternative though is to pay about 3 times as much for Aspen/Stihl motomix alkylate fuel.Both L it has solvency & lubricity , it can resolve minor carb circuit fouling short term & reduce oxidation & corrosion long term brother !
If any of these brews do what they say on the label, my saws and mower will be running well!