Pros: This unit is able to circulate and clean a decent sized room at the lowest setting.

Cons: The noise level above the lowest setting is higher than I expected.

Overall Review: I purchased the unit for a bedroom to help ease allergy issues. The unit works good in my 10x17 room on low and it just tolerable when falling asleep. When I move the unit a larger room and bump up the speed, the noise increase goes up quickly. The highest setting is somewhere near the sound of a vacuum cleaner. I'm happy with the unit overall, but the level of noise limits use.