Yes probably -snake oil- ha , but l do not put in much. Did finally get to use my new deluxe 30 efi and put her to the test (40 cm plus of hard packed snow), Will give some detailed pros and cons later. In all , l am satisfied.
I will admit that I have used Marvel Mystery Oil in some of my older 2 stroke weed wackers and backpack blowers as a fuel additive. Just a cap full or so. True story... I bought a brand new Echo BP500T Backpack blower off a guy who had run regular gas in it and seized it. Got it for $50. Drove 7 hours total to get it! I was going to use it for parts. Over last winter I kept adding MMO in the cylinder through the spark plug hole every week. I would try and pull on the recoil each time. Lo and behold after a month the piston started to move. Eventually it was totally free. Last spring I mixed a heavier oil to gas mixture than what it usually runs, 25:1, I believe. Cleaned the plug and fired it up. I smoked out the surrounding neighbors for a while but the thing ran and idled great. I slowly leaned out the gas / oil mix and it stopped smoking and runs great! My wife uses that one as it is lighter than my vintage Solo BP blower that was converted from an orchard sprayer to a leaf blower. I have even added a little MMO to the gas in my Kubota lawn tractor. If nothing else the stuff has a great history behind it. Burt Pierce and the Marvel Carburetor!