I have a Yamaha motor and Ring Free has been great. Of course, it's the OEM product. My motor used to hesitate and back-off a couple of times when I got on plane. After a "detox" and regularly using good gas and Ring Free, it's all been good (so far). As far as the "good gas" part goes, I was told that the Techron that Chevron puts in their gas helps boat motors handle the ethanol. I'm not a chemist and not going to debate anything, only that the Ring Free and Chevron gas have made a very noticeable impact. I was told that Shell was usually good gas too and I use Shell when I can't find Chevron. Luckily, even Zapata has a Chevron