not sta-set x
Sta-set x is not an optimal line for sheets. I sailed a boat once with the genoa sheets rigged with sta-set x, and it was very difficult on my hands. Neither did it turn well over the winches. The tight turns over the sheaves in your mainsheet tackle are even worse. I love it for halyards, though! Regatta braid is my favorite line for sheets; I love its hand and flexibility. If stretch is a concern, there are better lines. Regular sta-set is fine, and you'll find it on most any boat you look.