So I debated the formula ready one over this one. Formula ready was almost $100 so for half the price I tried this one. I boiled the water & waited to cook down. Took about a hour for the cool down process for formula with the fan on and lid off. Then I tested the water for accuracy. The cool down process was a little long but saved me $50 so I can deal. Worth the money. Always stays warm. I am going to change and boil new water daily.