I use the red stabil + 93 octane. If you use 87 octane, you will probably have a problem no matter what. At least here in NJ, where we have "special" gasoline, and special EPA rules.

I haven't used up my "Red" yet, but I haven't had problems.
Ethanol (alcohol) absorbs moisture from the atmosphere.

What I do is top off the tank to the brim after every use to reduce the "dead air space" to nil.
The more air space in the tank, the greater the air exchange as it expands/contracts from the day to nighttime temperature changes.
10% ethanol is 10% ethanol, regardless of the fuels octane rating.

I've got a 76 station close to me that's selling it's mid range gas - 90 - ethanol free. Use it in my small engine and motorcycle. It's a little pricy - but great for small engines.

http://www.pure-gas.org/

It will cost more. But your mileage will be better too.

FWIW, I once emailed Stabil and asked them that question, they said the regular stabil would offset ethanol. Personally, when I empty a gas can I add the stabil so when I fill it, I'm ready to go. Considering the relatively small amount of Stabil or equivalent you'll use in a season for small engines, it's cheap insurance. Also follow Bill's advice on keeping tanks topped off.

Also, I always run small engines dry at the end of the season, been doing that for years, even before "mystery gas" appeared.

If you do a search here on GW you'll find as many opinions on ethanol as there are posters. You'll also find definitive info on what ethanol does to small engines by those more knowledgable than I am.

good luck,

Ev

I give my OPE a cap full of MMO when I fill them up. On my sit down mower, I run the carb dry after every use. It sits all winter just so. It may crank for a bit on that first start, but once I get the choke set right, it fires off and settles to smooth runnings. I put a 6.5 hoss Chonda on my old snowblower. It has a steel tank. It starts very easily.I have the tank filled to the brim with MMO and red Stabil . I dont even care if the gas goes bad. Thats easy to fix.I dont want to to deal with a rusty tank.
Since I began using MMO in E10 gasahol, my carb troubles have mostly disappeared. 2 strokes get it too. Mix oil has stuff that seems to preserve the fuel.