I ordered this filter to use when outdoor air quality deteriorates due to wildfires. I'd like to have a haven to retreat to inside my home since my profession requires me to be outdoors during the day. I've used the filter a few times just to see how it works and get comfortable with it, though I haven't needed to run it 24 hours a day yet. Overall I'm very pleased. It's easy to set up, intuitive to use, and barely makes any noise at all--even when I'm sitting right next to it. I know it will be put to the test when it gets smoky outside, but I feel like I've made a good investment in my health and expect it to make me much more comfortable this year.