Air Purifiers

This is the description :

Cleaning the air in your home is easier and more stylish with the Honeywell Tower HEPA Air Purifier. The Lifetime Permanent HEPA-Type filter helps reduce up to 99% of airborne particles such as dust, pollen, cat dander, smoke and mold spores from the air that passes through the filter. Easy to clean, vacuum-able HEPA filters save you hundreds in replacement filter costs compared to replacement filter models. An electronic filter clean indicator illuminates to remind you when to clean the filter. A built-in ionizer delivers extra cleaning power and helps freshen the air that passes through it. The filter also features an antimicrobial treatment to help prevent mold growth on the filter. Ideal for medium size rooms up to 169 sq. feet (13x13) with 3 cleaning levels for quiet performance. Start enjoying cleaner, fresher air today with a sleek Honeywell HEPA-Type Tower Air Purifier for your home or office.

Permanent HEPAClean filter-never needs replacing
Helps reduce 99% of airborne particles such

It says it only fits a (13X13) room .. the room I want to use this for is a school classroom that is atleast 20X20. If i put this purifier in a spot i believe the air is at its worse, will it work for a 13X13 area from that point forward or does this product become completely useless when its in a room any larger then (13X13).

Also, i am trying to find an air purifier in the 0-0 for a larger sized room, so if you have other suggestion please list

I can’t remember if it was an infomercial, or on HSN or QVC, but it was a tower air purifier, it had no fan, but you could see that air would flow through it because they put paper on the front of it, I think it had a UV light and an ionizer, but no filter, just this thing that you had to take out of the center and wipe down.

What was this called?

And if you know if ionizers actually do something, or if they are just stupid please tell me that too

HOLMES HEPA AIR PURIFIER
IONIC PRO MINI AIR PURIFIER
Holmes Harmony HEPA-Type Mini-Tower Air Purifier

Only one of these 3.

I am trying to decide what machine type be best for a low to medium astma person and also another person that is allergy to grass after it cut.

Is a Hepa Filter Air Purifier the best one to get or a Ionizer.
I was planning on getting a Hamilton Beach 04491 True-Air Tower Air Purifier or the Hamilton Beach Air Ionic just needed to know which one be the best. The person is a 5 year old.

I know not all ionizer air filters create ozone, and I have pets that I can't have near ozone. Other ions are fine. I just haven't been using the "Performance booster" for fear it creates ozone. I have Holmes HAP412N-U HEPA-Type Mini Tower Air Purifier.

Thanks!