ORIGINAL: BarracudaHockey
On an airplane you probably wouldn't notice the difference unless you were replacing some old servo that you could time with a sundial.
Overcoming the intertia of the prop, and the ability of an IC engine to respond to throttle changes make it not worth the money.
I thought of that one after I posted. You still have to overcome the prop inertia - good on you BarracudaHockey.
Big selling point of digital servos is they return to null-point very precisely. That would be mid-throttle and a "so what" for practical value.
Do a good job of throttle linkage (short and unbinding) and you'll be much better for it. Proper throttles don't take much torque and a short, slop free run to a small servo is better than a long wonky run to a large one.