Product review (4 stars): Less expensive than many options but still requires continual cleaning.
I need to preface this that we have hard water and run three Honeywell humidifiers continuously. (Daily filling requires total water ranging from 3 to 9 gallons)  We do a major cleaning of the tanks and base at least every six months which includes Clorex.  We have used many manufacture's products.  We have found the BestAir Combo to be more economical than the BestAir for bacteria and BestAir for mineral single bottles.  The Combo works as well as any product or combination of products we have tried.  That is not to suggest clean up is simple.  We're tried adding the Protec Humidifier Cleaning Balls.  For us we suggest, save your money.  They didn't seem to help much either.  We need to had humidity as our GeoThermal heating/cooling system removes moisture making our dry climate an even bigger challenge.  We've tried whole house systems - we do not recommend this option.  Cleaning and maintenance is EXPENSIVE.  IF money is of a non-issue OK.  We are looking for an easier solution.  Where are the inventors?