Bought for my mom in a one-bedroom apartment in an older and somewhat smelly building. She has issues with the old building smells, living in a basement level apartment. After only a few hours of running, smells were gone and have stayed gone. No more issues with her stuffy sinuses and runs 24/7. Has been using the same filter for approx 6 months, she vacuums off the dust every other week or so and has no issues. Air in the apartment is fresher, cleaner and healthier, nighttime stuffiness is gone. Adjustable fan and light levels work great for her needs. Only caveat is this, the main unit is not as expensive as others, but the filters are more expensive. Compared to the Levoit, which I bought for my father, the main unit is more expensive, but the filters are less expensive. Both work equally well.