@sarae @mycorrhiza Winix filters show up on Woot all the time with a pretty good discount. The most recent one I bought has two pre-filters, one disposable and cheap and the second a washable plastic mesh. This works great for houses with pets. But I have several older ones, and they're fine, too. I will say that the fan died in one after about two or three years.
I also don't like the bright blue LEDs that can't easily be turned off. Requires tape or surgery to fix. A common problem, though.