I have tried multiple models, Oreck table top, Vornado Hepa & very expensive Molekule. Finally I subscribed to Consumer Reports and this brand (not specific model) was in top 2 of their list. We also wanted something with UV germ protection, so the price seemed right to give it a try. Seriously, Molekule was 4x this price & rated at 20/100 by CR vs this brand at 80/100.On the first day, I closed our bedroom door & put it on full power. I have terrible hay fever every spring. I just wanted a nap without waking up breathing through my mouth and miserable. When I entered the room 2 hours later (the room is about half the size this model covers, so 150-200 sq ft), it smelled different, very crisp, almost like being outside after it rained or an ice rink. I took a nap & 90 min later I woke up and was amazed to take a full, deep, bottom of my lungs breath. That never happens when sleeping for me in hay fever season. Since then, I've had the same results, all night long, as long as room is sealed by closing door.Yes, it's loud. There's no question on this and if you want something super quiet at full speed, look elsewhere. We like the white noise & even have an app we play for our son to help him sleep with waves, rain or a fan sound, so that is a plus for our family.And fair warning, it does seem to generate cool air. It's winter now & with our door closed the single vent for the furnace in our room with the door closed isn't up to the task of heating the space even without the air purifier (with bathroom + walk-in closet). This device pulls in air & blows it out strongly on full power. It was enough to mean we had to move it farther from our curtains so it wouldn't suck them in or blow them around so they fluttered. It's a strong filter which could be a big plus or minus depending on your needs. I wouldn't recommend it for a Zen meditation space, spa or massage room where you seek silence.Also, other reviewers aren't wrong about its ability to get rid of strong smells quickly. I'm not sure which air purifiers in this price range & sq ft size would. Give it time and it will eliminate odors, smoke, etc. much faster than no air filtration. We have a 1400 sq ft home that isn't well sealed in main living area (dog door, front door doesn't seal tight, windows simple double panes), so it isn't as remarkable except in bedrooms with closed doors. We bought two for a big room and main area + a few small ones for other bedrooms, then close doors to rooms we're not in, etc. With the right ratio of devices to sq ft, it's exactly what it claims. It does need to be on full power constantly to achieve the room size stated, but that's true of all air filtration systems. It's declared clearly in all the product materials and industry standards.After many models, realistic understanding of what home filtration options available can do well, I can definitely say this one is top notch.