Call me a fool, Lord knows many people have, but the only high torque servo I have ever used is the Tower TS-65. They're listed for $29.99 at the moment, but they are three for $85.97. Now if you order a few more things to break the $150 barrier, you get 10% off. Couple all this with free shipping and I make that out to be $25.80 per servo.

I probably have 15 of these servos, and they have never let me down. Dual BB with 77 oz of torque and they include a hefty servo arm. I have taken these apart and I can tell you they have stuffed the biggest possible motor in there, and the wide helical output gear is a thing to marvel at. You won't be breaking that one! They center very well, and mount in standard servo mounts.

I think they're Hitec HS-605BBJ servos re branded, but who cares?

I have them on the UCD 46 for rudder and both ailerons. I used two S3004's for the elevator, considering the small size of the surface.