There is a new little aerobatic model - designed by a long time aerobatic flyer - which uses a full span set of bumps at the high point of the airfoil top n bottom - th airfoil is quite thick with the high point well forward.
The model is 3 D thing sold by Horizon and utilizes the new AS3X stability system.
Videos show excellent stability at high AOA -
I have never tried this approach-but have used air dams which stop spanwise flow works well-
Maybe the super thick "ice cream cone" airfoil contributes the most to the good stability but the little generators may really seal the deal -
what do ya think - there are videos of this on HH site .