that_air_guy
cobra1999,
Your question is a good one, but it requires knowing more about your situation to give you a good answer. There are several factors to consider such as how much you want to spend, what you are trying to clean, how big of an area, etc...
There is a lot of information out there. Much of it is biased. Much of it is based on marketing. Much of it is questionable. Some of it is good. Research is necessary.
I have a website dedicated to simplifying the research on how to choose the air purifier for you. I am growing the site to address your question and provide non-biased information. This is not a commercial for my site, but you can see it if you click into my bio. I have a TOP 10 section for whole home purifiers.
Am I biased? Well, I certainly have my opinions ... On my site, I rank purifiers based on certain criteria... I do have my favorites, but this is from years of use and many, many reviews of other models.
There are other reviewers out there that would come up with a different list of recommendations. Take mine as part of your research.
Regards,
TAG