If you do go with them, I’d say just make sure you have a backup plan just in case they start failing to notify etc. Maybe one of the +/- 5% variance devices, as a failsafe. Being off by 5% is better than nothing!
I still use WST and it works most of the time, I just don’t trust it to always work (for instance, i had it monitoring moisture in plants. Well, it decided to just stop monitoring and I had a very dry plant before I had manually checked.) Basically I treat them as a secondary reminder at this point. If something is important it’s always good to have two independent readings anyway.
One other thing, you might be able to use the Fibaro RGBW (which has analogue inputs for temp/etc) or the Fibaro Door/window sensor which I know can monitor temp if you add a DS18b20, so one would think it could do humidity as well.) Just a couplel other options to look into. I believe the 18b20 is close to +/- 1% and those can be calibrated.