I have one of those ethanol-friendly diaphragms in my YF3211S. It is on the second year currently. 4 years ago I had one I was testing but I sold the carburetor and left it in there (clumsily). I've purposefully let the carburetor go dry several times...no problems so far. And yes...I use ethanol gas. It is treated with Sta-Bil 360, and if that's what is keeping it alive, well...that's cheap protection. I bought 3 or 4 when a fellow had them on eBay, but now he only has the common black diaphragm.
