To my mind, acoustics is as important as cooling ability. I have two boxes here and with a sound meter they both give the exact same reading. One has the Thermalright Silver Arrow, the other has the Phanteks PH-TC14-PE. I have to focus my attention to hear either them but the Arrow "seems" quieter .... I'm guessing it's because the sound is at a lower frequency so it's not as close to the center of human hearing range, it's less intrusive.