First off, the purifiera blow out cold air. I just did not expect this. I was expecting fresh air but not cold. Given that it's winter, it's probably a bigger issue for me than most. Second, it's louder than expected, even on sleep mode, so my family didn't want it in their bedrooms. And, third, the purifiers do not qualify for EZ return so if you don't like it, you have to pay to ship it back and it's very expensive! Not worth the money.