In theory you're supposed to match the direction of spin your fletchings impart on your arrow to the bevel (counterclockwise - left bevel, clockwise - right bevel.) I would imagine that you may not see that big of a performance shift if you are just flipping sticks at targets, but would see the difference in on-game performance as you'd begin your cut with the dull side of the tip. Admittedly, I haven't killed anything with these (which is why they are so handsomely beautiful) but that is how they work on paper.