Short on features With so many people working from home due to COVID-19, smart air purifiers have become a hot item, but they can get expensive. If you don’t have room in your budget for a high-end model like the $549 Dyson TP07, which features a 360-degree HEPA filter and doubles as a fan, the $219 Proscenic A9 is an attractive, much more affordable alternative. This four-stage smart air purifier filters out airborne allergens, pet dander, smoke, and pollen, and it did a good job of scrubbing the air in our tests. That said, it’s a basic model that lacks the extensive air quality measurements and extra features you get with more expensive models such as the Dyson TP07 and the $499 Aura Air.