Dude, this cooler is DEAD quiet!
I installed the fan controller that came with it onto the back of my case, so I could adjust the RPM. Looking at my monitoring software, all the way down is like 1200 - 1400 RPM, and max is about 2500RPM. I can't even hear a difference, turning the knob between the two. It's DEAD quiet I tell you.
It's a pinch to install, too. I've always recommended it, but after actually owning one, GET IT!!!
Get the one with LED's though...
EDIT: By the way, I'm going to completely re-do my wiring tomorrow. I will update this thread with new and better pics.