i'm a little less concerned about accurate co2 levels, since mitigation is straightforward (open a window). even imperfect co2 readings are good enough to signal when to open a window (around 800-1000 ppm, or ~2x ambient co2 levels).

voc's and particulate matter are more my nemesis, as my lungs are more sensitive to that stuff. beyond knowing generally how bad the air is, i'd like to be able to figure out what is causing the bad air and how to mitigate it. information there seems lacking right now.

i'd trust the radon sensor in the airthings more than the voc/co2 sensor, since radon is what they're known for. the voc/co2 sensor is probably the cheaper type used in most consumer air quality monitors, so it's good directionally but is not strictly accurate/precise.