I have a 2007 ls Cobalt and so far I have a nice sound system and a K&N cold air intake, 2 halo projector headlights and smoked led tail lights. I am now looking at more add ons for it? But mainly I want a new exhaust I want a catback but not sure about anything else?? I Don't want it to sound like a Ricer or be loud that everyone is looking. I just want a nice sound and I want it to raise my HP. Im willing to spend up to $550 bucks but let me know what you think.