I purchased this air purifier because I have very sensitive allergies to mold, dust, pet dander, and many other particles. Before purchasing the air cleaner, I was sick very often from my allergies. My allergist recommended I purchase an air purifier and I chose this one. I have not been sick from allergies since I purchased it. Besides working great, I like how it has a sensor with different colored lights to let you know how clean or dirty the air is in the room. I also like how quiet it is. I often leave it running on high while I sleep, and I never have any trouble sleeping. It is sort of like white noise in the background. The sound from the air cleaner dampens sounds from other rooms or outside. I recommend the Winix PlasmaWave for anyone with allergies or anyone who needs cleaner air. Ease of Maintenance It is not hard to change out the filters. Dust/Allergen Removal As far as I can tell from my allergies, the air cleaner has gotten rid of almost all of the allergens. Filter Availability I have not had any trouble finding the filters. Durability My dog has knocked over the air cleaner several times, and runs into it often. So far, the air cleaner has not been damaged. Effectiveness The air cleaner is very effective. It has helped my allergies tremendously. Design The design is pretty good. I like how the air comes out of the top, so it is not blowing directly toward my furniture. Instead it goes up and circulates around the room. It is kind of large, but for how well it works I do not mind the size.