Petra's Tech is the local shop i go to since it like 5 mins from where i live (yes i am fortunate). i asked the guy about the specs on this fan ( i didnt believe it) and he oferred to turn it on in comparison with a Nexus.
the Nexus fan is actually still quieter then this fan, but barely. The Sflex fan is basically the same noise level, with a tiny bit more of a pitch, both are really silent. However, the sflex fan pushes more air than the nexus. I mean i have no real data to back it up, but with a simple hand test i felt noticibly more flow with the sflex fan. I would buy one but i already own a nexus.....
i would use these for my case fans and heatsink if i went aircooling, but for radiator, how bout the higher speed version that blows 60+ CFM since the radiator is somewhat restrictive. Didnt get to hear this one so i have no idea how loud it is. Also, with these fluid bearings, are these fan ok to undervolt?