How loud is it you ask... here are some attempts at answering. Keep in mind that the topic of discussion is inherently subjective.
1. Loud enough that I know it's there but not so loud that I wish it was not there.
2. While crusing in any gear it is not so loud that it in any way interferes wih conversation or the stereo but upon acceleration I get a nice sporty growl that grabs the passenger's attention without being unpleasant.
3. Not as loud as standing next to a blender whilst you make an ice cream shake.
4. Not as loud as standing next to a full size cappuccino machine letting of steam. (Howeve the exhaust doesn't smell as good as the cappuccino either.)
I'm picking one up up from dayjay for 400. I'm looking forward to it. Brullen web site has it for like 950 bucks. This one has about 16000 miles on it. It's the quiet one. I'll try and figure out a way to record the sound inside and out and post. I'll record it in stock and 93 performance courtesy of APR in about two weeks.
Its definately softer than the Borla. I had a Brullen in my car, and Blownaway gave me a couple rides in his Borla equipped Passat. I think his exhaust is .25 inches bigger than mine tho. With my Brullen at idle, I wouldnt notice I had an exhaust unless I really try to listen for it.