Probably //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif Your car is light, any power increase should be noticeable.
A catback will reduce the backpressure of your exhaust system, making the engine have to "work" less to expel burnt exhaust gas. However since it is a N/A car, taking the exhaust off completely would be a bad idea as you need
some backpressure or else your car will get really confused and you'll lose power.
A GOOD-SOUNDING catback will make you happy every time you drive. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif Having a manual car that sounds good is something that cannot be emulated. Every time you take off from a light and people look at you, not like "Ew that car sounds like crap! RICER!" but like "D@mn... That's sexy.

" that's such a good feeling. Plus you can rev and have it sound good. It's a no-loss mod; you only benefit from it. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif Just make SURE to find one you like BEFORE buying.
edit: plus it lets the world know that you are of the elite group of people who drive stick //content.invisioncic.com/y282845/emoticons/cool.gif.3bcaf8f141236c00f8044d07150e34f7.gif Everyone can hear you shift.