Take a look at the Leo Vince SBK. There is a video on YouTube somewhere, just not sure at this second. It's the quietest (according to pipecity.com rep) and comes with the dB reducer already installed (which can be removed if you want louder). The dB reducer for the CS One is about $35-40 extra.
Having said that, I will likely go with the V&H with the reducer when I decide to drop the money.