Saw a few good reviews for these fans. The things that caught my eye were the high static pressure, linear fan speed and startup voltage that has these fans started at just 300rpm. Great I thought, so I purchased a whole lot for a couple of systems I'm watercooling. So, yeah, all those things I mentioned are great. Except for one major problem; the fans have really poor build quality. At least a few of the fans I have will rattle either constantly, or when the fan speed is above 600 rpm. I have a couple in my HTPC that buzz. Thankfully I can run those at so low RPM that the buzz can only be heard with your ear against the case but still WTF?