I was just reporting what I do, and have done. I always have had lots of gasoline powered gear. When they started adding ethanol, I always thought it was one of the biggest and most expensive boondoggles, ever to hit the marketplace. And I would describe myself as an environmentalist tree hugger.
Of late I have had many mechanics repeatedly tell me, that ethanol is a problem for carburetor rubber and plastic parts, and have not missed the fact that they sell five gallon drums of ethanol free gasoline for 16-20 per gallon.(At lawn mower stores) I just ain't gonna pay that much for dinosaur juice. The kid at the airport who fuels airplanes, says a lot of people come and buy avgas for their lawn equipment.
I guess I don't believe in additives since I have never used them and haven't really had a problem. I actually was fairly well satisfied using Amoco Ultimate in my equipment. Their advertising said it had an extra refining step that made it water clear. I guess it is just that,I am susceptible to different advertising {;o) Part of it is I don't have a clear understanding of what Stabil does and how it works. (except see below) I also am pretty sure that running Ultimate in my lawn equipment was a complete and utter waste of money but I did it anyway :lol:
I have had headaches with carbs gumming up. Only on a Toro two cycle snow thrower that didn't get used for several years and I probably left gasoline in it. Running things dry seems to prevent most problems. I just started with the avgas so if a four cycle valve or ring sticks because of the lead I will report back.
You can find out more about what is in these products(ie Stabil and Seafoam)by checking their MSDS (material safety data sheet). Mostly they consist of petroleum distillate(s), naphtha, and Isopropyl alcohol which will help ethanol mix back with gasoline.