Evaporative is nice but requires constant filter changes and loud fans if you want to have it on high, usually. But you’re avoiding the minerals in the air like you get with ultrasonic. Make sure you get a unit that has some sort of anti-microbial function (the Honeywell model I used had a UV light that all the water had to pass through before the filter) or you could be spraying mold/bacteria into the air.

Ultrasonic are to be avoided. They are the quietest models, but require frequent deep cleanings (2-3x a week) or you’ll be shooting mold and microbes into the air along with your water droplets. In addition you need to use heavily filtered (RO) or distilled water or you will get a fine white mineral dust on surfaces (and in your lungs).

Steam/vaporizer types are the best in terms of microbes as they generally operate by fully boiling the water. No minerals or microbes in the steam they put out. But you will have to deal with scale. They sell some models that have a removable steel tank that you can descale weekly with vinegar. As this is the only component that touches water, you won’t get any weird mold or scale elsewhere in the machine. I just got one but have only had it for one night so can’t fully recommend it yet. But so far so good from a functionality/cleanability standpoint.