yes it is definately loud. no bad attention yet. if i don't let the turbo spool it's fine. i have a 3" full exhaust with a cat and muffler. i'm going to actually replace that and get a new high flow cat, resonator and muffler to quiet it down. it doesn't matter since i have this 3" boost activated cut out right after the down pipe:
it doesn't open up till about 5psi... after that it gets super loud
i bought it used from a guy who got the kit from turbo concepts, not sure what he paid but i paid $1200 for the kit and i think he paid a few hundred more brand new.
i haven't really messed around with my boost controller yet (maftpro) but this is the dyno when it made 16psi just using the spring in the tial wg: