I ve owned two of this and both times the bacteria/fungus resistant sponge had mold on it..
Seems to work very well in a small humidor. Uses cheap distilled water, no expensive PG solution.
Doesn't work, at all. I soaked the sponge in distilled water as instructed and it did not put out any humidity. It's a piece of metal, two cheap plastic end caps, and a white sponge. I can't understand what exactly is $45 about it.