The shape of the leading edge has alot to do with the way a airfoil reacts in the air. The way I understand it a more blunt leading edge helps make the wing more stall resistant. If the shape of the wing on one side is different it will make one side stall before the other or in other words snap. The elevator on the Edge 540 is very efficient at stalling the main wing for 3D but if the wing does not stall evenly the plane will snap.