After about 4100 rounds, my Gen4 19 experienced two malfunctions in today's 250 round session. I was shooting Federal American Eagle 124g ammo, with the 04 recoil spring. Here is one of the malfunctions:
The extractor seems to have a lot of wear on it, it doesn't drop out of the slide easily. It seems to be binding a bit on the striker block (during removal). This one has a "3" on it. The "4" I picked up from VA Arms, it doesn't bind on the block.
Unusual wear:
Number "3":