The power supply is functioning well and certainly is not extremely loud, but it was not my case anyway. You can hear a slight rattle, which for most people is indeed probably bearable, but for me, as I have on my PC permanently and usually work without music and noise because it was just annoying after a while.
For not so sensitive to noise and music listeners: buy it quiet. For people who want a silent PC as possible: a look at it at Cosair who actually silent power supplies.
