Top Tier Gas question

From a driving standpoint I haven’t noticed any difference in any gas as long as it’s 87 or above. I just put 27k miles on my 22 since May 2 on a trip from VA up through Canada to Nome AK and all points in between. Even got filled up from a 55 gallon drum on the northern range up towards Barrow. I think that was Exxon. A five oil change trip and I used what I could find. My 25 gallons of backup in the bed was all from Shell in Montana. The 14k or so before the trip was the same. Yes I’ve put 41k on it in 8.5 months.

 

Ethanol free 90 octane is what I like to run
Mileage is consistently 21-23

 

I would prefer to run the ethanol free gas, but the only station close to me that sells it is a Circle K. They are not top tier, so I’ve been sticking with Mobil instead with their 10% ethanol.