If pure water or Reverse Osmosis water is used then it will solve the problem of mineral build up. I never have any mineral build up!

I have a warm one but I will be moving to a cool mist or ultrasonic due to the load on my circuit.

Having the space heater and the warm humidifier on the same circuit causes the breaker to trip. I don't have the option of running another circuit at this time so I will change over to the cool type this season.