Hi Mickey, I've seen the videos of your designs. They have a good realistic speed and appearance in flight. In my opinion, a speed range of zero mph (hanging on the prop) to @ 30 mph would approximate realism for the average sized model gyro. I am talking no-wind conditions. Also, I am making a comparison to the original, full-fuselage style autogyro. Some Bensen-style machines will cruise at a higher scale speed than, say, a Pitcairn or Kellet. How slow can you go ??? Let me know !!! Thanx !!! Charlie Anderson