We use a 2 gallon SPT ultrasonic to help supplement our whole house humidifier in the arid winters in CO. It’s lasted 2 years running full time in the dry seasons before the fan went out. Found out it uses a common server fan so I bought one for $10 and had it up and running again in 10 min. Love the thing. It’s lasted longer than any other humidifier we’ve owned. And it’s the easiest of all to clean.
I've tried several over the years and the SPT 2-gallon is the only one which holds up against our hard water.