I have been using Tru-Fuel or similar. My local Lowes and lawnmower shops have it. At the last or second to last fill up of the season I run Tru-Fuel through and thus far zero issues. I used to replace the carb on my Hinda mower almost yearly. Honda had such an issue with ethanol the carbs now run me about $16.00 but the first one about 8 years ago was $130.00.... I switched over to Tru-Fuel for off seasons after I began running Stihl 50:1 pre-mixed fuel in my weed whacker, chain saw and leaf blower. I also now keep Tru-Fuel in my Honda EU2000.. Since I began using this type of product not so much as a hiccup. The stuff has a shelf life of 5 years if unopened and two years once opened. Not cheap but cheaper than the alternatives....

During the season I just use regular fuel and Marine Stabil in the dinghy motor but the last fill of the season I run the Tru-Fuel through them. I just buy it by the case...