I think the issue deals with trigger geometry--I am not sure if it is limited to the trigger shoe or all of the trigger components working together. I notice that on the 43x, and I assume the 48, the trigger shoe is serrated, compared to my G19. I do not like the shoe design so for $22 .00 I ordered a trigger shoe, that was Glock Oem, but it comes modified in a few respects--one, the shoe is smoothed and not serrated and the trigger safety sits flusher to the rest of the shoe when pressed another claimed modification impacts pre-travel. I am going to utilize the 43x trigger bar which I have polished up and am interested to see if it makes a difference. If not, I may also experiment by installing the Apex almost flat face trigger shoe with the Glock trigger bar and/or and Overwatch flat face trigger with the integrated bar.