My Nec 2510 is very quiet...
But the Benq 1640 isn't loud either.
You can use Nero Drive speed to control the speed and so the loudness.
In general I watch DVDs with my Aopen 1648 regulated to 4x with DriveSpeed, this is absolutely quiet.
There's a region-free firmware for the Aopen aswell as for then NECs. (for all NEC's, besides.) I heared that there's also one for the BenQ.
The Nec can do bitsetting with hacked firmware, is available in black, is cheap (abou 45â‚¬) and has excellent writing quality.
The Benq can do bitsetting with stock firmware, is available in black, is cheap (about 50â‚¬) and has good writing quality.
So -> NEC.
Hope, this helps.
P.S.: Welcome to cdreaks!