As I mentioned above I avoid making comments about engines I have not owned, I've seen guys fumble with some of the best engines you can buy, most engines are only as good as their owners tuning abilities. I still have one of each size of MDS engines from the .48 up to and including a 2.18 and about a dozen Fox's most have been flown except a couple of rare .15s and a new .46 that I just put on a H9 Cessna 62. I tried everything to get a fourstroke on it but they're just too long, Enya .53, OS .52 and Saito .56 and .62, all no go.