I used to live in China a decade ago and everyone used ultrasonic humidifiers there. When I moved back to the US, I searched for one of them and could only find steam and evaporative humidifiers like this Honeywell one. Having small children, I went for the Honneywell humidifier and hated it - I was stupefied that it had such good reviews. So I searched for "safe" steam humidifiers and couldn't find one, so I gave up.

Last year, I noticed that ultrasonic humidifiers were now very popular and cheap on Amazon, and got one. The review sites recommended against them, due to supposed calcium and bacteria build-up, but I haven't seen any problems, and the Honeywell was definitely worse on these fronts.

Get an ultrasonic humidifier - they are cheap and if they break, you can get another one. Just used filtered water in them.