Hoop hit the nail on the head...magnetics & coil designs is an art, and there is quite a variation in the level of quality in commercial AND military designs. If looking at the aftermarket, do your research...price and quality will vary, and a low production item like aftermarket stator design does raise the question of where the quality goes.
HD item has the advantage of plenty of R&D behind it and improvements are an ongoing thing (part of their "hidden under wraps" design philosophy) so look at revision level of the new part, if buying HD...! And if they have it in stock, compare the old to the new part...you will be surprised.
HD item has the advantage of plenty of R&D behind it and improvements are an ongoing thing (part of their "hidden under wraps" design philosophy) so look at revision level of the new part, if buying HD...! And if they have it in stock, compare the old to the new part...you will be surprised.