If the Kadet you're going to build after the Cub is a Kadet Senior I would use the 3010's on it everywhere except the throttle where the 3004 is fine. The size of the surface area being moved into the airstream and the potential speed of the model is the guide for what servo to use. I have used 3004's on a 71" J-3 Cub and 3010's on a Kadet Senior, a Rascal 110, and many 81"-90" Cubs with success. Good luck with your Cub.