How do you top up the sealant? If you can unseat the tyre, pour it in and re-inflate with a track pump then there's no need to unscrew the valve core and top up that way.
I have 3 sets of wheels and have tried 3 different types of tyres and find this the easiest way.
I've never injected into the valves, should I start doing this?
I've literally done all my tires with a jug and a track pump