Product review (2 stars): Not nearly as effective as the originals
For some reason, these just don't soak up water from the reservoir as much as the original filters that came with our Bionaire humidifier.  At first, I would leave them in with the humidifier on all day and, upon checking the filters in the evening, there was plenty of water in the reservoir, but the tops of the filters were still dry!  Our room remained quite dry and uncomfortable through this period.  Our humidifier has a sensor that detects moisture at the tops of the filters (to indicate when to replace old filters), which has been pretty consistently giving a negative reading.  However, after a couple weeks of frustrating use, they seem to be working just a little better these days.

Also, wtf is up with the packs of three?  Had to buy two packs to round it out, so I'll be stuck with these crumby filters for a while, but will surely be looking for a different product next time we need filters.