Product review (3 stars): Still wondering if it makes sense
The humidifier itself is the best we have so far, quiet and reliable. We purchased it more than 4 years ago. My question is whether or not the filters make sense. I mean, you can buy for less than $30 a humidifier that runs without any filter at all, there are many brands available. While this one will eat up 1 filter every month or less depending on the type (and quality) of water you get at home. We use it only at night, every night, during winter season or as long as the heating is on. I empty the tank every  morning and I clean it either with Clorox or diluted vinegar once a week. Still, by the beginning of the third week or sooner, you see the black spots (fungi) in the filter. By the end of the same week it smells. For some reason I prefer this filter over the one we use in another humidifier we have (katz). Although the life spam of both is very similar.
I want to believe the $7+ I am spending on every filter give us a cleaner humidity than the humidifier that runs without filter. Although so far nobody was able to confirm this to me.