Just one point, anyone who recommends a standard type servo for mechanical retracts is not quite on the ball.
Too many ways to come undone, and the saving on the servo's will probably cover half the cost.
And if your going to this expense, may I ask, why are you not putting good pneumatic retracts in her?

Are you using a simple Rx, or are you running one with more complex features, such as servo balancing, in which case you don't need the programming capabilities of the servo.
Do you really need digitals on the flaps? Metal geared?

They quote a pretty hefty servo for rudder, which might be fine on an aerobat, but in my experience the warbirds are pretty light on rudder forces, and rarely need metal gears. And does it need to be digital?

Ailerons and elevator I always go for the best I can afford, and always metal gears in ailerons.

Throttle, never metal gears but I would go for bearing rather than bushing, but this can depend on the type of linkage you have to the motor, ie: a bowden cable saves a lot on your servo but solid wire linkages are much harder on your servo.

Just some thoughts to throw into the mix.

Mike