I agree with carbking
Up in SK we have sometimes low blended ethanol but you can’t know for sure day to day
Pump label states up to 15% ethanol possible
But so far the gasoline seems to be AD truck ideal blend
Never water
No damage to rubber or non metallic parts
Power piston in carb stays free
Truck will start just fine after 6 months on a 1/4 tank of old gas
I buy exclusively from the co-op which has its own refinery/upgrader facility in Regina SK, perhaps they control their process better suited to our region and use cases.

I was buying premium from the shell station for my Audi however they have their own upgrader in Alberta and my car had trouble adapting to that fuel and I would get Engine Power Control warnings usually in the fall on cold starts near freezing temperatures
Since switching to only co-op premium for the Audi and regular for the trucks everything got better
-s