Pros: Very high CFM. At full speed (2000 rpm) you can hear it but its not too loud to be irritating. At 1400 rpm still moves a lot of air, yet its nearly silent, at about 2-4 feet away.Great fan, have one in front and one in the rear of the case and all is cool and quiet. Nice subtle blue glow too.

Cons: None.

Overall Review: I know its a three pin connection but if your montherbord comes with a four pin plug you can ajust the speed percentage in your BIOS to get the fan to run almost completly silent. I run mine at 60% and my video card and power supply get loud enough to hear but not these fans.