Not loud.. Flows nice Volant!! Hands down for the price and quality.
I can't speak for magnaflow, but price is lower and quality is top notch. Not sure if they still have the special, but you might want to look into it. I got my complete catback for $225.. While your at it, have them hook up up with an intake too.
The sound is comparitive to stock. A little rumble, but pretty comparative. When you mash the throttle, the rumble is def. there, but nothing that's going to turn heads which is a good thing "for me".
I made a post of what the exhaust looks like installed. Only took about an hour with no directions. It was easy. I did mine with my grandfather, but it can easily be done alone as well. Nice little garage project.