I've only been using this for a couple of days but I am really pleased with it! My dust and mite allergies were getting the better of me in my dusty 19th century house with horse hair plaster and forced hot air heating. The first night I took this out of the box and plugged it in, there was an initial chemical odor that went away after about an hour and then....clean fresh air! Very efficient so far. I moved it from the living room to the bedroom and woke up the next day without the stuffy nose I usually have all winter. It's a relatively compact size so even though it must be three feet from the wall it's not overly obtrusive. The noise level is acceptable, it's about the same as a fan or an air conditioner on low. It feels solidly built (Honeywell/Kaz has generally produced good products in that regard). And the price on Overstock was the best I found anywhere online at the time of purchase -- gotta love the O!