I've had my air purifier (Holmes HAP243) for over a year now and I can tell the difference in the air from room to room. The air is fresh clean seems silly but a little cooler, I have it in my bedroom so I can sleep comfortable with knowing the air that I am sleeping in is being purified.

The replacement filters are also easy to change and when you see what was in your air that is in the filter give you relief to know that your air purifier is working and removing all the dust,pet hair and just the stale air other things not seen.