If your using digital servos on everything else, you would benefit by using a digital on the throttle. Josey Wales followed up well with what was started about throttle servo speeds and types, and his experience with the differences are the same as I experienced by changing from analog toi digital. To qoute "You can feel the difference!".

A super duty digital with a lot of torque is wasted in the throttle position, but one that is both fast and accurate with relatively low torque ratings would be perfect.

Pat