A great unit for the price, but it does have flaws.

First thing, this unit exhausts straight up, so the review that says it exhausts to the side must be a different air purifier.
This is a great filter. We had to buy an air purifier for my wife's asthma - an allergy to cats, and she loves our cat, so . . .
  I went to lots of sites and reviews to research the topic. Most tended to diss smaller units like this one in favor of units costing 500 and up. I don't know about you, but that's a big chunk of money in our house. The reviews also tend to prefer the HEPA type a/p over the ion/electronic air cleaner type.
  As for the expensive units, we have a ranch-type house (two levels), so what I did was to buy this filter (HFD-130) and a Honeywell 50250. I decided to take a chance that two inexpensive filters would do the job. I couldn't swing buying a single filter for closer to 1K, much less two of them!
  Both Honeywells have been running constantly for about a year now. The 50250 is upstairs, covering about 900 sq ft. The HFD-130 is downstairs, covering slightly less, but the cat spends most of his time downstairs. Both are doing a fine job of keeping the air clean, and my wife has no asthma reactions to the cat. The HFD-130 is running on the medium setting, the 50250 is on low. The 50250 does have a higher sound level than the HFD-130, but on low or medium it is not unpleasant, and we watch tv sitting right next to it. I can't hear the birds singing outside as well as with it off. As for the HFD-130, right now I am sitting at my computer, and the computer fan is noisier than the HFD-130 sitting 8 ft away.
  Here is where the 50250 beats the HFD-130: maintenance. The 50250 comes apart easily for quick vacuuming, or a filter change when needed. The HFD-130 is a semi-pain when it needs maintenance.
  HFD-130 works very well, but does have some design issues. It has a lightweight plastic rear panel that could be easily broken. A MAJOR design flaw, imho, is the air intake area. There is a pre-filter hair catching screen, which is great. But, it is locked inside a plastic grill section, with no provisions for cleaning it!!! In my experience, this area required the MOST cleaning of the whole filter. It uses Torx(tm) driver screws to fasten it, which are a complete pain to undo if you want to clean this area. Without cleaning this area, after a year of use, I would have to throw away the whole unit as used up! With cleaning it, I should see many more years of filtering!
  The electronic filter area is only moderately difficult to clean, not too bad, but the plastic parts are, again, lightweight and probably fragile. I want to say flimsy, but they are just a little better than that - not much.
  Bottom line, we are very happy with both, both are an excellent value, and do what we bought them for. The 50250 probably filters more air than the HFD-130, and certainly is far easier to maintain.