Don't forget that on a cub with scale ailerons, if you use them as flaps you will *increase* the risk of tip stall. If its semi-scale and has full span stip ailerons then I wouldnt worry.

The HS-225 servos should do ok. I've stipped the plastic gear version on 40 size 3D ships and wont use them in that application anymore, but on up to 40 size sport planes with smaller surfaces and throws they do great.