Avalon 5L Ultrasonic Digital Humidifier

I have purchased many humidifiers to compare them to each other. I was primarily looking for one with the least sound. This is the winner by far. While it is not silent - as none of them are - this at least didn't have the high buzzing ultrasonic noise. I ran all of them for 3 days to compare water deposits in the reservoir and around the ultrasonic mist generator. The filtration of this unit was also better than the others. The display is pretty easy to figure out without reading the manual (which is rather confusing first because each button is indicated with a letter then each letter describes the button one above the designated one - but this was my only problem so it's not a big deal.) Not paying attention to the manual first I accidentally figured out that this unit also makes warm mist. This is a bit overkill for me not being a true warm mist, since it doesn't generate the mist by heating the water over the boiling point but just warms it up before it gets to the ultrasonic atomizer. However, I have to point out that I have a real warm mist humidifier which is still louder than this one. So I sent the others back and I bought 3 more of this to each room. I ques that sums it up.