I have used both Apex and Galloway, not just once but twice (same order, two guns, same exact experience).
Installing the Galloway kit was just like swapping used factory parts for used factory parts; no change and certainly NO improvement of any kind. Trigger pull scale did not really change either. I asked them why I did not see any improvement and their response was "If you don't like it send it back for a refund". Definitely not the product they advertised it to be.
My experience with Apex was the opposite. Made a noticeable difference for me. Plus their customer service is much better as well.