ive run my MDS .40 on my trainer on 10% Model Technics with no worries (MT was the only fuel i can find with 18% oil), getting near half a gallon through it and the plug (OS #8) doesnt show any sign of wear and i havent had any trouble with pre-ingition or anything, can be a bit of a pig to start when its hot, but when its running its fine

trouble with the four star .60 is our runways are relatively small as the field is mainly for electrics, so i think a .60 would struggle to takeoff and land in a small runway