I have (and use) the 503 T in several of my planes requiring a high torque servo on the rudder. For sport flying you will be OK. They are slower than other servos, but unless you require the high speed (3D, precision flying) you PROBABLY will not really notice the speed difference. One plane I have them in is a PacificAero Gee Bee Y, 86" span with an OS 160FX. I have not had any problems at all with them.