Bests & Worsts Reviews from Amazon

Update 1/2020: Dropping my review to one star; the fan in this unit started making a rattling noise that is very audible (and very annoying). ---- I bought this back in September 2017 to help cut down on dust and allergens in a smaller studio apartment. After living with it for a year and a half, I think it works well enough, but I don't think this product is deserving of the rave reviews that it's been getting. Here are my main criticisms: 1) Not actually that quiet: The fan is nowhere near as quiet as a larger model. Additionally, it doesn't move as much air. Some of this is just basic engineering: this unit is so small, so naturally it has a smaller fan inside than a bigger unit would. Consequently, the fan has to turn at a higher speed to move the equivalent amount of air as a larger unit. When running on low, this unit has a dull hum in the background. I picked up a second unit, a Winix, that you can not hear at all when running on low. The Winix moves almost as much air on low as the PureZone does on high. 2) Annoying pre-filter: Pre-filters on air purifiers are (normally) similar to the filter screens you have on a window AC. The idea is that they catch the big chunks of dust/hair/etc and prolong the life of your HEPA filter. On this unit, there is some type of velcro-attached pre-filter that you are supposed to be able to detach and clean regularly. The problem is this pre-filter is made out of a felt-like material, and pretty much disintegrates after being removed and cleaned a few times. The velcro tears apart the material every time you remove it, and it releases a big cloud of dust (so you have to do it outside). It doesn't last anywhere near as long as the actual filter does. 3) Short-lasting charcoal filter: The charcoal odor-filter in these units is integrated into the main HEPA filter. As a result, you can't replace it separately. The charcoal filter doesn't last anywhere near as long as the HEPA filter does, so you'll either be wasting money replacing the entire filter much sooner than needed, or just have to accept the fact that the unit won't remove odors very well. While I'm still going to go ahead and keep the unit as it works "well enough" for my needs, I don't think the trade-offs are worth it - especially given that the list price is comparable to much better models. If you absolutely 100% must have something small despite the negative tradeoffs, this unit is probably the best option. Otherwise, step up to the more reputable and effective Winix. I paid 20% more for the Winix than I did for this, and the Winix included a 2-year supply of filters (did not purchase the Winix on Amazon).