Very old thread but I must say, every one is wrong, MDS stands for Many Dead Sticks!!!! I still have a couple of them, one .58 is almost new in the box. I had one .68 that ran pretty good, when they ran they were power houses!! What I did find out {too late} was they liked FAI fuel better then what we run here in the states. I was using 15% and they hated it. When I tried 5% they ran better, a lot better. My bad, if I would have sat down and given it some thought I would have come up with the easy answer, they are made in Russia and nitro cost too much to be using so give some FAI a try. It still didn't mater much, the engines castings were so bad they broke just from the mufflers weight and vibration. If I make up a new run in stand I may get the ones I still have running again and see if anyone wants them. The .68s were for some reason better then the .58s?? Both running and castings.