I am a smoker, I live on a first floor and I am always concerned about the amount of soot/dirt, etc that comes into my apartment. Not to mention, many of my friends do not smoke so I need something that does double duty!

There are many air purifiers and ionizers on the market, and I've tried several of them with varied degrees of success.

Initially my thought was to purchase one of the 'never replace the filter' type and I did that (at Home Depot) for a fairly reasonable price (maybe 90 dollars). I used those for about 2 years until I discovered that although I vacuumed the 'permanant' filter monthly the darn thing wasn't working as it should.

About a year ago I purchase a pair of Holmes HAP422 (tower style) for my apartment and I am pleasantly amazed at how well they work.

They have on them a filtering system that actually lights up when it's time to replace them, the replacements are cost effective (they come 2 to a box), and I've only replaced them one time in the year.

Not only do I not have a 'smoking odor' in my apartment but I've also discovered that those tiny particles of crap that come in through my windows are now not all over my furniture and windowsills.

I strongly recommend this as one of the most cost effective and efficient units.

As an added point of interest it does have 3 speeds, it's a circulating and it's got a nice small footprint.

I've been very happy with mine!

Good luck in your search!