I have a set of PXG irons first generation. I have tried their subsequent generations and didn't gain anything over my set or like the feel. I also have Sugar Daddy wedges 50, 54 and Zulu 58. Unfortunately they are becoming like all the other club makers with a new generation every 2-3 years. Not as bad as Callaway (hate) or Taylormade (Neutral).
I really like these wedges, unfortunately PXG stopped making them. So if I need new clubs i will be back to Titleist, or Ping.
I still have 1st gen PXG driver - gained 10 yards. If i need to replace I will try a different shaft rather than buy new one. I have retired the 3 and 5 woods for a Titleist 4 wood and hybrids.
I am becoming convinced that new shafts can resusitate a club you love and don't want to replace.