Bring back the SmokeStop filters already.
First off: Some other reviewer talked about the smell of bleach or an odd odor, and uploaded a picture of their purifier next to what appears to be an IQAir filter. If they're running an IQAir, it contains permanganate, which will impart the air with what I interpret to be a slightly sweet smell. This is NOT a BlueAir issue, and the machines DO NOT PRODUCE OZONE. PERIOD. Anyone who says otherwise is either a liar or a moron.
Also, these filters ABSOLUTELY work. You can simply measure the PM2.5 in a room with them running, and see that they make a difference. And no, DO NOT run a purifier with only one carbon filter installed. It does nothing because, as BlueAir explained, the air will just move through the other filter with less resistance.
That said, I'm unhappy about BlueAir discontinuing their SmokeStop filters. With those fitlers, you could then couple the Carbon+ filter, effectively getting some filtration from VOCs and the like. There isn't much carbon in these filters to begin with. Compare these filters with an IQAir, which contains like 12 pounds (!!!) of activated carbon and permanganate. You may not love the smell of permanganate in the morning, but it certainly cleans the air.
So seriously. Just bring back the SmokeStop filters already. I'm sure there's some perfectly kromulent business reason for why they were discontinued, just as there's a reason that Google sunsets every project it touches. But just bring them back for a limited release. Put them in a…