In Stabilator vs. Elevator, the stabilator provides more maneuverability because of the larger moving surface while having less drag.

Elevators and a horozontal stab are a good economical setup, and are self neutralizing, (the airflow makes the turn surface return to neutral).
Stabilators need to have the pivot point near the center of lift so the forces required to move the enormous surface are low.
There are conditions where the center of pressure on the stabilator moves forward of the pivot point, and will not return to neutral by itself without the assistance of a moveable tab called, (odly enough), a "servo".

Horozontal stabs are generally stronger, lighter and easier to setup compared to stabilators.
There are many full size aircraft that use stabilators for maneuverability, like the F15, F18, and yes, even the Piper Arrow.
In radio control, you would need to have a much stronger servo to move the stabilator enough to have the same effect as a horozontal stab and elevator.

Is one better than the other? I think that in model aircraft it is just personal preference, unless you are building a scale model and require a specific setup.
Some of the 3D planes have such a small horozontal stab and large elevator that they almost act as a stabilator with leading edge slats.

I guess the main thing to remember here is - Pull back, plane goes up - Push forward, plane goes down.

Bob