In my experience the Schwalbe tubes have been notorious for coming with faulty cores. I have been replacing them with no-name cores from AliExpress, that both looked better by eye and operated without problems. I hope the replacement cores marketed by Schwalbe are of a better quality than those in the tubes they market.
My own experience has been different. I have used at least 30 Schwalbe tubes that get pumped at least twice a week and get used for 3+ years most of the time. (I patch rather than replace). Never had a PV go bad but I rarely have an issue with any brand Presta valve. To the OP, maybe you don't need to get spares yet. If you already have some spare tubes just use the valve from one of them and when you toss an old tube, save the PV for spares. I'm a bit frugal that way but always have spares for friends and people who have destroyed. theirs on the side of the road with ham fisted pumping after a flat.