Product review (1 stars): I can't agree more with the review below: "The ...
I can't agree more with the review below:

"The problem is that the filter beads absorb any amount of water in the air - even inside the sealed packs they arrive in - and swell, so that you are trying to coax swollen, wet, sticky beads into a small annulus of the cartridge without getting them into the center"

It is a pain in the ass to fill the cartridge without making huge mess, it sticky, so it gets on everything and everywhere, including your hands.