For Silent PCs not really recommended

As expected, the air flow rate is really higher than comparable fans, but I can not confirm that these fans "very quiet" are on low speeds. So if the right to a Silent PC has to be screwed together should possibly look for another fan. Who is the volume matter and it's all about the air flow gets here a good fan.
For comparison, the BeQuiet in my system since 09/2010 ongoing four fans (Silent Wings), which are quieter and run quieter than that of Corshair served.

After two months in operation with 7V (approx 12h / day) have the fan started to "rattle" which I feel very disturbing and these have now taken by the current.
I will once again replace the two fan against the original fan my Fractal Design R3 or get me two SilentWings.

Too bad, really had a lot expected from the many good reviews.