I have been using this Bionaire air purifier for about 8 months and have had no complaints so far. This month the red indicator light came on which I assumed was for replacing the filter. Replacing the filter was very easy. Revain sells the filters for $25 for a two-pack, which is a really good deal. I noticed nasal congestion and allergy symptoms decrease within a month of purchasing the product. It quickly removes smoke and other unpleasant odors. I like 3 settings, although I mostly use medium and high settings. Some people are picky about noise, but medium settings are just a low hum, and high settings are obviously a bit louder, but I still find it useful for blocking out outside noise. Overall I think this is a good product for the price.