fuel stabilizer

I think Seafoam does a good job. I use in my small engines.

For the Southwind, I've been using Sta-bil marine for the last few years. Works good, no problems.

For long term storage I always use Sta-Bil in fuel tank of motorhome. Like you, I excerise the generator once a month as well as cranking the motorhome. Occasionally, I will take it for a short ride.

If gasoline, start with non-ethanol fuel if possible. You can find it in most areas, but it's usually on the expensive end. www.pure-gas.org is a good resource for finding it. I'm keeping my own page for locations in Utah with a focus on how good RV access is to the station.

In the past I used StaBil. They quote a year for storage, where Sea Foam quotes two. I've used Sea Foam in my Jeep before and had good results, and switched to it for storage of gasoline. Run the engine for a while after adding whatever you do to let it get into the fuel system. Then exercise it periodically.

Sea foam or Star-tron

small engines, I use AVGAS.

For my cars that will sit, Marine grade Stabil

I used to use Sta-Bil but have switched to Seafoam.. Several reports of issues with the first convinced me to switch.

100LL Avgas for small engines and Lucas in everything else.

I use Stabil for stored fuel, and Seafoam spray for occasional carb cleaning in small engines. Stabil can be used at 2x the recommended amount for storing gas 2 years, which is what I do for my "strategic reserve" for the home backup genset.

Sta-bil marine in all my gas cans and the motorcycle.
Stihl 2 stroke oil for the 2 stroke stuff. The saw sits with gas all winter as I never know when I will have to cut my way out of the driveway.

All my small engines get E0 (non-ethanol) gas. After I drain the tank and run the carb dry, I put some 2-stroke mix in the tank, run it through the carb, then drain the tank and run the carb dry again. The 2-stroke oil 1) has stabilizer in it and 2) I figure it keeps the carb gaskets from drying out.

I had to tear down and clean son-in-laws weedwacker carb this spring after he let it sit all winter with E10 in it. Coincidence?