My mathews and reflex are shooting zebra twist strings, and my bowtech has the winners choice.
I think the key to non-peep rotaion for me has been using the string loop to align my peep. At rest they all sit within a 1/8th rotation of truely faceing rearward. In fact I do believe the bowtech and reflex are facing 100% rearward.

No tied in nocks and no brass nocks.

On my champion, the string sat facing 90 dgrees sideways, but at full draw would pull the peep true. I have no idea what strings it used.