Exhaust isn't bad at all, It came with the bike when I bought it. The exhaust really isn't that loud at lower RPMs, and sounds pretty sweet when you go WOT.
Nice thing about devil exhausts is that if I want to later on I can purchase headers which will fit right into the slip-on cause they use stock mounting points. Also I get to keep the passenger pegs. I used to have a SV 650 which ironically had a scorpion carbon fiber slip-on, pretty much what my friend has. That exhaust was pretty loud but sounded badass. On his bike the scorpion sounds a little higher pitched and is somewhat louder than mine.