I remember I was at the sport airport with a .40 size Decathlon and I was trying to make some simple scale like aerobatic patterns that I could train on, at the same time the local club J3 Cub was pulling gliders every now and then and I noticed the movements of that and tried to compare it to my model airplane. And I got to the conclusion that my model was never going to be able to fly slow enough, but I still think that when I look at a scale plane in the air I don't primarily look particularly at its airspeed. I look more at how it moves, and that have a lot to do with how the pilot of that model fly his plane.