been using ml 140's for a few years and there a lot quieter than the original fans on the h115i or the old case fans, not to mention they can all be pwm controlled and run at super low speed only problem is you can kill the bearings if your running them on variable power or upside down meaning i was limited in which way round i could set up my pc's air movement and needed a sata pwm splitter since my mobo only had a single pwm header, a minor annoyance rather than a giant expense