As much as I can I use nothing but non-alcohol premium treated with a triple dose of Sta-Bil in all small engines. It has never failed me yet. Put the additive in before you fill the can and it doesn't have to be stirred. Just pumping it in agitates it plenty.
The cost of the gas is nothing compared to the cost of getting the carb rebuilt like my friends have had to do, and some have even thrown out otherwise good lawn equipment from having the gas go bad. The frustration around here is that there are not really that many good small engine mechanics. Anyone can hang out a shingle and after 3 or 4 trips back to the same shop to get a carb fixed right, they just give up.
20 miles to get the right gas is nothing compared to the time to take the engine back a few times.
The only exception is my generator in hunting season where it is not possible to get non-ethanol premium. Then I have to rely on the triple Sta-Bil and that seems to work, although I try to run that gas out of the generator right after the season is over and get the good stuff in the tank and carb.
Now, why do I put Sta-Bil in gas that I know I am going to use up completely this week? Well, many years ago I had a family emergency come up and I had to put down the saw I was using and take care of an extended illness. When I got back to the saw, a few months later, it was trashed. The cost of the stabilizer is very low compared to the cost of new equipment.