Product review (3 stars): Works ok, but expensive
These are half the price on Holmes Website.  Thankfully, someone else pointed that out previously.  So, for the value, I don't understand how anyone could give this a 5 star rating.  We blow through 2 of these each winter, and they used to sell in a 2 pk (for $20), so keep that in mind when ordering.  One will likely not be enough.  We use ours every night from about November to March.  It would be nice if these would last a little longer.  Oh, I should mention that we have a whole house water filtration system/softener.  I would think that would keep the hard water from building up so quick, but they do get funky quickly.  When desperate, this can be cleaned/rinsed and put back in, but they kind of start to fall apart when you take them out.