Yeah i think the fans are quiet but because there pushing so much air THATS the "noise" that you here, so its not actually the fan motor, but my 200mm top fan died 3 days ago so ive just got the 3 120mm fans and another 120mm on the side window, so my pc is almost silent now(120mm fans on low) and my pc temps are fine so im not going to bother getting a new 200mm fan
Ps, nice mod, i know its annoying taking the cover off to change fan speeds, especially if like me you have the pc under a desk, which means i have to pull the whole thing out and take out all the wires so i can move it onto my bed for closer inspection