Oneup posts have been great for me, if not a bit on the noisy side from some rattling. They do have different diameter keyway pins, which helps, but Ive maxxed those options out. Two of them still working relatively well after 2+ years. I do miss the Bikeyoke I had sometimes, much quieter, less jiggling of the head of the post and saddle. Interested if the PNW post has a leg up on the post jiggle game. Never ridden one but installed a few, good looking/feeling post.
I find the new fox post leaves much to be desired. They do feel nice in your hand, and when they work, they work well. Unfortunately the shop I'm at has seen a pretty high percentage of warranties for the IFP, and the fact that its still pretty heavy, expensive, offers no adjustability, and moderate length:drop its a solid "meh." If it comes stock on your bike, its still a great post, just maybe not the best deal if bought separately.