the nf-f12s are really good, i've got 2 in my rig at the moment and with the low noise adapter they are literally silent, at full volts they aren't quite silent but are virtually so.
If you don't like how they look, well then perhaps mount them behind the radiator so you can't see them?
If you don't like how they look, well then perhaps mount them behind the radiator so you can't see them?