I have run my PX4 extremely dirty. 200 rounds of filthy, corroded, ~10 year old ammo followed by 200-250 of modern ammo. When I cleaned it, it took a LOT of time to get all the grime out. It never hiccuped. In nearly 2k rounds, it never has.
14 Pistols, 5 Rifles, 1 Shotgun, no time to shoot them