That's right China rubber and alcohol do not mix. Best to buy gas the end of Winter before they raise the alcohol they put in.
In all my gas cans 2 and 4 stroke I use Sta-Bil, keeps all the nasty stuff from separating, for up to a year. I use AMSoil octane booster also. Best bet is Home Depot, 94 octane premix 50 to 1 alcohol free chainsaw gas. Going to try to add booster to that and see what happens, lol.