I also got a few of the Airthings View Plus boxes, one for each floor of the house and one in the bedroom specifically. Learned some very interesting things, such as that when the A/C comes on at night, the VOCs and CO2 spikes so we were able to address this properly. As an SRE style person, the idea was that without observability into the current state, we didn't really know where the problems were or what we should do to fix them (though perhaps the solution is always just "buy an air purifier").