Buy the air cleaner with the highest room cleaning/hour rating you can afford.
The ionizer actually makes asthma worse, so you don't need a model with this feature.
I have a nice Kenmore Hepa Supreme Air that does a lovely job of cleaning the air. One in the living room and one in the bedroom. I only run them when I am in the room for any length of time. Seems to help a lot. Was told to do so by an asthma doc. Been using them for years.
By
02/21/2007
Now finding one that REALLY works is the hard part!
By
02/21/2007
Sears keeps filters in stock for discontinued models, so you won't have to pay shipping when ordering new filters in a few years. Every few months they have a coupon in their flyer for 5% (or more) off of anything in the store. Even better!