Hi bigjoe,
I think the people that fly the large scale models do use spoileron when doing the harrier. It's been my experiance with the 40 size profiles that it makes them wing wobble much worse than no ele/ail mix at all and some models harrier good with the flapperon mix you have.
With the Super 7 you may have settle for a fixed spoilern setting when you move switch c down. You can program spoileron to elevator when you move switch c up but you wouldn't have flapperons then.
With all the 40 size profiles i've flown, spoilerns and the harrier don't work.
Happy Harriers