They are comparatively very loud! And because of the 3-pin connector, they cannot be controlled via the mainboard!

I don't own this case but I also own one from Corsair. My standard built-in fans are very loud, BUT here are other fans inside (with LEDs) and I suspect that the HD120 RGB are installed. You can read for yourself how the volume etc. of them is. The case is in no way insulated, there is glass everywhere.