Once again, I'll be the contrarian. We use 4 HEPA room sized filters in our 2 homes. We had purchased CR top-rated filters around 10 years ago, and after time, the vendors were gone on one brand, new models had come out on the other and we couldn't get parts.

So, I looked for something that would - give good if not top performance, was widely available and had a long history behind it, used the same filters over a wide range of models.

I settled on the Honeywell Insight series, tried one for a year, and found it easy to use and maintain. We now own 4 of them in 3 different sizes. I buy the filters directly from Honeywell, pre-filter by the roll and cut it easily to fit each machine. Identical HEPA filters 12 or 20 at a time depending on price.

After 4+ years I'm a satisfied customer, one machine was noisier than the others, they replaced it without question after 7 months.