I just recently (March) purchased a " Hunter" from Bob Lee archery, I was suggested by someone else, to use left-hand helical 5 in. feathers.
I have been shooting righthand helical for about four years. I was at the range yesterday shooting those left-hand helical feathers on an Axis 500 carbon arrow, I was smacking arrows together, I hit the spot I was looking at more with my left-hand helical than I ever have using my righthand helical. Now it could be the fact that I have new bow, and it is a recurve instead of a longbow.
But I happen to think it makes a difference. You just have to find out what works for you, given them a try, if it works you've accomplished something. There is no set rules that apply to everybody. That's what I like about the freedom in traditional archery. You don't have that with the other wheel stuff. When you try different things in traditional archery and it works out, you know, that you have, accomplished something, not the equipment. Your equipment is only an extension of you in traditional archery.
Pastor Carl