I snagged a really nice levoit purifier during the wildfires, along with a PM2.5/10 sensor to verify its operation. Works great, even when the filter is "up" it still reduces by 95%~. I can verify this is functioning by turning it off and frying with the windows shut.

The filter lives in my bedroom where I figure it's doing the most good by giving me cleaner air when I'm sleeping. (maybe 1/3 of my life, so cheap investment in PM reduction!)

I strongly suggest getting an independent air quality meter that shows actual numbers. Speaking generally, the meters integrated in the purifiers are not trustable.