My experience with the Apex spring kit might be a tad different (my perception) than what other people are having.
I purchased my new SD9 VE last weekend. I did not find the trigger pull objectionable; actually, it was a little better than I was expecting. According to my Lyman electronic trigger pull gauge, the average weight was approximately 9+ lbs. and long, but fairly smooth.
I placed an online order that same day for an Apex spring kit and it arrived very quickly. I replaced all three (3) springs following the Apex video and lubed per their instructions.
After completing this modification and firing ~100 rounds at the range, I remeasured the trigger pull with my gauge. The weight reduction was not as great as I expected... after several measurements, the pull ranged between the high 6 lbs. to low 7 lbs. with no change in trigger pull distance and/or trigger break point.
I had hoped for a solid low 6 lb. trigger weight.
ONE NATION UNDER GOD