It's quite good, tie-to-tie with the 300W unit from SeaSonic.
Get there:
http://www.silentpcreview.com/module...rtid=28&page=1
A coworker of mine has just bought the Seasonic, once he's back from lunch i'll tell you about his feelings.
(note) besides Seasonic (and i think Zalmann as well) make 'silent' units up to 450W.