RE: rudder servos torque
Presuming that you are going to use it in your F-22, there is a neat servo from Futaba : the S3050
that is metal gear, digital, 90 oz/in at 6v and dead cheap. (don“t know if this matters to you) plenty
of torque for a knife edge loop if the airframe is capable of it...
Rgds, Enrique