It works great and efficiently! Quiet enough that you don't really noticing it or not bothering at all. Easy to switch between different modes depending on what you need. I'd definitely recommend this product!
I got this as a gift and I was a little concerned that it might be too loud. But I was pleasantly surprised. I don't even know it's running unless I kick the fan into high gear (I'm not saying I burned dinner one night, but it did get a little smokey). I have terrible allergies and asthma, which is why my son gave it to me and I have noticed a difference since I got it. Fewer attacks means a better quality of life.
Compact footprint, good feature range, very quiet. The two-stage carbon + HEPA filtering is a nice touch. They refer to the back cover as a "washable, microscreen pre-filter" but with 1/2+ inch square openings, there is nothing "micro" about it. Smallest thing it will keep out is your Chihuahua.
Physical device setup was simple, but deducted a star for the horribly convoluted app pairing process which took 8-10 tries to complete. Problem is the unit is 2.4gHz wireless only and if you have 5-6gHz wireless (like about 99 percent of the users out there) you have to temporarily cripple your local network to the lower frequency during the pairing process. Sharp - it's time to bring your devices into the new millennium.