Product review (2 stars): No real savings
I tried a few of these this past winter, they were great for a couple weeks, but once the minerals, dust and so forth in the water start accumulating, the filter does not work as well, and after the 3rd or 4th week, basically the humidifier was running non stop and 5 to 10 percent less than the set point, which was 40% RH. I used 4 filters this past winter, compared to 2 of the originals the previous year, so no savings after all.