This unit does a great job at throwing moisture into the air, which is, clearly, it's main purpose. It's fan is fairly noisy, and the reservoir holds only 9/10 of a gallon with the cap filter attached. It's very easy to put too much water in, and then have an overflow when replacing the cap. The tank volume is insufficient to run on "high" for a full day. That shows the amazing performance of the humidifier's capabilities, but the tank is just too small for my needs. While there's rarely room for improvement in a Vornado product, tank size would be the exception here. I'm considering a non-ultrasonic Vornado purchase. This humidifier seems to be a hiccup in the ever-amazing Vornado product line. I'm sincerely satisfied with every other Vornado product in my home.