Pros: This thing definitely moves a ton of air. Dropped the idle temps on my Phenom II x4 965BE 4Ghz OC from 34-37C down to 24-25C with a CoolIt ECO Liquid setup. And only about 52C now under full load! Was getting up around 65 before!

Cons: Very loud! Comparable to having a scale model jumbo-jet flying next to your head when at 100%. BUT - Also installed these with the NZXT Fan Controller (under $30), and at 40% power, runs about as loud as my old fans did at full RPM, with cooler temps still (around 28-29C).

Overall Review: The noise is not that big of a factor when compared to the massive airflow. Honestly, at full it's about as loud as your average household fan on low-medium. If that's something you think you can deal with, and need some extra cooling, then don't let the reports of noise deter you from picking these up. Even if noise is a bit of an issue, fan speed controllers are pretty cheap and work wonders for the sound levels off these fans, without sacrificing much performance. They really are great fans.