I personally don't believe ionizers are bad. All they are doing is charging the air particles so that dust and other particles attract to each other and fall to the ground
or other ones work with the principle that dust and dirt are attracted to the plates themselves, such as sharper image purifiers. There is always controversy on any new technology. I believe that air purifiers that only have filters are not so great. Using filters with some of the other technology would be a better choice, in my opinion. I would not just take my advice though. Research all air purifiers until you feel comfortable with what you are purchasing. The site that I researched a lot at was