Product review (5 stars): I'm commenting on the functionality rather than price- This does ...
I'm commenting on the functionality rather than price- This does what I needed.  I've always had a very clean house but would still get a musty smell when using a humidifier.  I've tried several treatments and this is the first one that actually works.  After months of daily use, there is no odd scent.  I put at least 3 or 4 gallons into the air per day and it always seems fresh.

Don't forget - you do still need to change filters periodically.