i'll have do redo the mod to really notice it myself. As said, to long of wait time in between mod and too short in there to really get to know the modded PU.
anyway, i swap the hexes on the plain string back and forth with filisters and there is a tiny difference. the hex screws are indeed a tiny bit more clicky on the attack, but it's too small of a difference i really care. On the other hand, on the wound strings on the neck PU it really does make a difference!