Noise is one of the hard specs to classify. In my opinion this is ok as long as you don´t hear a loud beeping you approach other people in the street. Only boards that could be described this way are the Yuneec boards and the Stary. What do you think? What are your expieriences?
What I noticed is that basically all newer boards with hub motors are pretty silent. Thus in the long run, for a silent ride, probably hub driven boards for the win.