There's not a whole lot of reason to go non-scale here. many people think that split flaps only cause drag because of the boattail area they cause when deployed. That is not true. They are aerodynamically similar to plain flaps at low angles of deployment, making them usefull even for takeoff flaps. At higher angles their drag increases over that of a plain flap making them very good for landing too. I have an A-4 that I bought in primer- I will be adding the split flaps before I fly it.