They are audible at 40% and louder above that, however you can run them at a lower fan speed and they are silent. They have a decent static pressure too.
If you know how to tune and tweak, they are good enough fans tbh.
They get a bad rating in reviews as they are using the performance BIOS and in that mode, you can't lower the fan speed below 40%.
Anyone with a modicum of intelligence can just switch to the Quiet BIOS, lower fan speeds as low as 25% if required, and increase power limits via MPT.
Maybe so but out of the box with a 360mm rad you'd kinda expect it to be silent considering some of the third party air cooled cards are barely audible. They just half assed it on the fans for the rad with that card.