I too have sworn off OS in favor of Evolution. I was impressed that when I first started it was PERFECTLY TUNED! I still richened it up 2 clicks just because I felt funny running a new engine that lean, although the company states that it has been broken in at the factory. One note on propping the .46NT skiman762 is running a 10X6 which is way too little prop for this engine Evolution recommends an 11X6 and the engine runs perfect with this setup (I can hover a 5 LB plane). However I have tried running it with an 11X4 which is too little prop, on a dive it sounds like the engine will explode from the revolutions. Also I now use an 11X7 as I like speed and it turns just as well as the 11X6. A note on Supertiger engines: A number of people at my club have had issues with poor carburetion on the new Supertigers they are swapping their new carbs for old ones from burnt out engines in order to get an engine that will transition properly. So I wouldn't buy one at this time.