Apparently, rounded leading edge with a thicker side profile has advantages over bevelled leading edge of the aeilerons. For the rounded ones, it seems that the eddy currents build up under the gap takes longer to expose its negative effects. So, if I were to go for rounded ones, I will properly make one that looked like an oval shape than round, to lessen the effect of hinge interference during hinge rotation while achieving the advantage of round LE.