Forgive me if this is a major misdirection, but it was my understanding that the original airbox was designed to muffle the turbo flutter sound. My 360 sounds like it has an atmospheric BOV (I just have theCBV on the 13c), yet the donar 940 was dead quiet (auto box and factory airbox would've been the main factors IMO).
The recurculating bypass valve option is a good option as it will serve as surge 'protection' and make it quieter, but it may still be louder than you prefer, depending on your boost levels. Compressor surge isnt really a problem at low boost levels and decrease reliability seems negligible from what I've read.
I believe the best set up for installing a recirculating valve is to have the inlet side on the intercooler piping close to the throttle body and the outlet going into the pipe feeding the turbo. Ive been looking into this myself and it seems this setup is the best way to protect the intercooler and turbo from the surge of air flowing back to the turbo, but I think there are other ways of setting it up.
So the recirculating bypass valve is a good idea. Or you could possibly look into airbox mods. Or both.