The judging in all the classes go along the same lines. Other organizations pretty much use the AMA rules modified mosty to speed up judging; I believe Scale Masters skip the bottoms. Remember, be there to have fun first; not everyone shows up with a perfect plane, and some times it takes refinement. What you see and what the judge is looking for takes some practice. The best part is everyone is there for the same thing, having fun with their scale airplane.