Many sites go about rating air purifiers based on quality, price, or reputation. However most fail to include important information such as:
1) Particle tests (video)
2) Video reviews that take you inside each machine (so you can see the filters)
3) Comparison charts that also include warranty info and replacement filter costs
To get the best air purifier for you my suggestion is to first watch the video below. It explains the ten technologies and which each one does.
Once you know the technology for your needs then go to the comparison chart to look for models that match. Then watch the video reviews on these models, particle tests, along with the pro's and con's listed in each review.
1) Since each air purifier covers a different amount of square footage, many consumers buy air purifiers that are underpowered or overpowered.
2) Each of the different types of air purification technology helps something different. I have seen, for example, people buy an Oreck Air Purifier for seasonal allergies, only to discover that without HEPA it won't do a thorough job on pollen or dust. Again - watch thevideo above on teh ten types if you don't know them, and what they do.
3) When rating air purifiers even consumer reports fails to include replacement filter costs. EX: If you buy one of the best-rated air purifiers (the IQ air purifier which costs $899) you'll be paying $190 every 6-9 months for the replacement filters(The comparison chart shows the replacement filter costs).
You'll see the filters inside each air purifier model by choosing the models from the left menu.
The Air Purifier Expert