Product review (5 stars): Good Product
Good product works as advertised and shelves are fairly flexible for different storage combinations.  As reported by others this unit is does not run completely silently.  However, I do not feel it is loud enough to cause concern unless you plan on using it in a room that is meant to be completely silent.  The sound it makes is similar to some radiant heat systems with little tings accompanied by the tinkle of water gently running through pipes. I do not think you would hear it if it was installed under a cabinet etc and the normal everyday din of a busy room drowns out the sounds it makes.