I use spoilerons for all 3d maneuvers (full up elevator puts both elevators up about 40% of full travel. full down elevator puts both ailerons down about 40%).

I find it helps to hold the nose up in harriers and it makes it easier to get into a knife-wedge spin. It may also reduce the wing rock tendencies.

I have the spoilerons on a switch, but I leave the switch on for weeks at a time (take-off, landing, general flying around, 3d, etc.)