Sealant is just liquid latex. Different brands will have their marketing hype, but I haven't seen any difference. It only works with small punctures, generally under 2mm. ymmv.

I use it after the puncture, not in a preventive way. On the road I carry sealant and a spare tire. If the sealant doesn't work, I'll put on the spare. Any flat where sealant doesn't work goes to Tire Alert.

But 95% of my flats occur when my tread is paper thin and then I just pitch the tire.