I see some familiar people here, hello! I'm a fairly long time MMO user, a tradition passed down from decades of dad using it. I recently tried TC-W3 and for some reason like the MMO better in the gas. The engine seems to run well with either, but I have given up slight mpgs with the TC-W3. I also noticed that if you give too big a dose of TC-W3 the engine lacks some power, where as you would have to go hog wild with the MMO. Just my observations, YMMV.