A bushed .40-.42 will fly this plane quite well if built light. For more performance and more vertical a BB .40-.53 will do wonders. If you want to go four stroke, a .52-.54 will do it if it is light and a .70 will fly it nicely! Brands these days don't amount to squat...just about any modern engine will perform just fine once it is set-up/properly tuned.