The QC on your ball valve takes the most abuse since it gets exposed to the chem's more. I'm one of those that will on occasion use the ball valve only to spray/rinse. I change these about twice as often than others. Usually the female QC lasts longer than the male. Over time the flow erodes the bottom where the male QC seats to the o-ring and the pressure causes the ball bearings to indent the lip on the male QC. I replace the male end about twice as often as the female and I always put in a new o-ring when I do. Make sure you change o-rings at any QC you see leaking, the spring and balls get exposed to the downstream mix and they will degrade or even lock up. I use WD and hit all the connections every week or so, the main QC on the ball valve I hit daily.