They work with just about any receiver, the receiver really doesn't know if the servo is digital or not nor does it care.

The reason they center and hold better is because they develop full torque almost instantly where an analog servo will be nearly to its stopping point before the motor reaches full torque.

Lastly the programming. This comes in handy because you can reverse them, set the end points, set the center and even set the speed all without a fancy radio. Centering is nice as you can get a very precise setup without dialing up a bunch of sub-trim. Where a programmer comes into its own is when you have a large plane with multiple servos per control surface, you can exactly match full throws, center, and speed to keep the control surface from binding during its throw.

If you're going to do 3D they are nice. On a Cub they wouldn't make much difference.