I've only been running it for a few days, but the air feels cleaner in our bedroom and I wake up less congested. It was really easy to put together (I did it at 9 at night in about 10 minutes) and packaged well (easy to get into). It's quieter than the older 375 model. I also use it for white noise and need to run it on the highest level to have sound masking noise -- I don't consider that a bad thing. I got the expresso brown panel because we have dark brown-(almost black) -stained post and beam and it blends in perfectly. Very thin and unintrusive. Happy with it! I have had the 375 (and still do--still running great after 6 years) and so far am equally as pleased with this one--hoping it lasts as long as the other one has lasted/is lasting.