Pros: Cleans the room indeed. Have not cleaned the pre-filter at all since day 1 and it still cleans the air in my room pretty well. Works pretty good as a secondary source of air conditioning for cold air.

Cons: > Makes a buzzing noise on level 1 cleaning, had to readjust the positioning to prevent such noise. Maybe I got a semi-bad cleaner? Oh well not a big problem anyways.
> Indeed higher levels/speed of cleaning gets louder.
> Dries up the room. I have a computer in the room, and it makes a lot of heat. Dry air + warm air from PC = electric static discharges = NO BUENO (especially for electrical equipment). I always get zapped here and there from time to time when coming into contact with my computer desk, I think the zapping may have damaged my mouse too. Had to resolve issue by buying an air humidifier to balance out the air for a safer environment for my PC.

Other Thoughts: All in all, I would recommend this air purifier. Although it seems to not be able to clean the dust getting into my PC, it still keeps the air around my room clean. All what really matters is that it keeps the air clean really, it was designed to clean the air not designed to be an automated duster that eats up all the dust in the house that it can find.

Pros: Can vacuum the filters, three speed settings

Cons: I got this specifically because there's a smoker in the house. I wish I'd read the first review here before buying it. He only smokes in his bedroom so obviously it's in there, but I haven't noticed much of a difference even though it stays on high speed.

Other Thoughts: It may work fine for clearing dusty rooms, but I really don't know. The high speed is a tad loud, but he actually likes the background noise.

Pros: Very effective. Turned it on as soon as I got it, and it cleaned up the air in my room within the first 3 hours. I have asthma as well as a recently acquired cat allergy. We live in a dusty old house and we have a lot of cats so I wasn't sure if this was going to be effective, but the very first night I used it, I could tell that I had not wasted my money. The air smells very clean now, and the best part is I can breathe at night!

Cons: None so far.

Other Thoughts: Some reviewers commented about noise. It is a little obnoxious on high, but it's not really that bad. I find medium is a completely tolerable noise level, and low is whisper quiet.
Also, the manual says you are supposed to replace the filter every 6 months (unlike what the website says) but I haven't owned it long enough to know if that's actually necessary.

Pros: Powerful, PERMANENT filtration, and very effective!

Cons: The fans are a hair noisier than I had expected on levels 2 and 3. At low, they are whisper quiet however. Not worth knocking an egg off in my opinion.

Other Thoughts: Living in Arizona, the air conditioning is on a good portion of the year, and as such dust can be a pretty big problem. As our family has grown by 1, we felt we needed to do something about the ever-growing air quality problem in our home. (HVAC filters aren't cutting it)

This has been a really good solution, and the air is noticeably cleaner/easier to breathe. We wake up with less stuffy/runny noses, and my computer isn't gathering nearly as much dust after putting two of these in high-traffic areas. I can recommend these for those with young children or dusty homes without hesitation. :)

Pros: put it down stairs next to the cat box! it has greatly helped with the smell

Cons: none

Other Thoughts: since i dont really know much about the air purifier's i cant really say much, but it does push a good amount of air, about the same as a cheap box fan.

Pros: Nice unit, no smokers in my house but I have it set up in my home office where I do computer repairs. Room smells much cleaner. Dust from other peoples computers made this room the dustiest of the house, filling the vents in my PC's in a day or 2... Let it run for a few days, then cleaned my computers and 3 days later, no build up.

Cons: none noted

Other Thoughts: loud on high, very quiet on low. I put it on low when I am home and turn it up when I am out...thinking about getting a couple more for the rest of the house.

Pros: Good form factor, low price.

Cons: HEPAClean is not the same thing as HEPA. "HEPA-Type" means it gets close to what a HEPA filter would do, but doesn't quite reach the mark. Newegg should not show the filter as "HEPA" in its specifications.

Pros: fairly cheap price wise and best part is no filter replacement !

Cons: fan on high is kinda loud..

Other Thoughts: fan on low is perfect to sleep by if you like a little background noise..

Pros: I live in an apartment with three cats and two ferrets. It does a pretty good job of keeping the odors down. The noise level on low speed is hardly noticeable. Permanent filter that vacuums clean.

Cons: It has three speed settings. At low speed the noise is hardly noticeable, about the same noise level as a desktop PC. On Medium speed there is a lot more noise, comparable to a plugin fan. High speed is just obnoxious.
It's ugly. You'll have to hide it before guests come over.

Other Thoughts: Not having to buy filters is nice, you simply vacuum the filter to clean it.
Perhaps I'm a design snob, but these air purifiers would not fit alongside anyones interior fixtures. It basically looks like an oversized air conditioning vent from some modern car. If it resembled a home theater speaker, (a black box) it would be more aesthetically pleasing.

Pros: Kicks a lot of air. nice filter design.

Cons: does not help much with smokers, but it keeps the dust and other oders down pretty well. and can be a little loud if it's close to where you work and on high.

Other Thoughts: Over all I am pleased with the two we bought. The price was right!