Is there any real performance gains to be made from changing that stock exhaust
 

Is their any real performance gains to be made from changing the stock exhaust and if so, i want a real deep but not too loud that its annoying. But i want you to know i am coming

RE: Is there any real performance gains to be made from changing that stock exhaust
 

This depends on what you change:

The mufflers themselves (aka "axle-back"): Changes the sound, but has no appreciable effect on performance.

Cat-back (mufflers + overaxle tubes): Same as above, but costs more.

Midpipe (X pipe or H pipe): If you get one with high flow cats it's worth a few HP, or an "off road pipe" with no cats is worth even more. Both will make your car louder. Offroad pipes, of course, are not street legal.

Shorty Headers: Worth anywhere from 3-5 HP. (not worth it IMHO, due to the cost and labor involved for such a small gain)

Longtube Headers: Worth anywhere from 15-25 HP with a tune, usually requires a new midpipe. (Many LT header kits include a new midpipe as part of the package). Worth it IMHO, but can be expensive depending on what brand you buy. Figure anywhere from a few hundred $$$ for painted steel parts (Hooker) up through $1400 or so for a top-of-the-line kit with highflow cats in stainless.

...there are many header threads, if you want more info hit the search.

RE: Is there any real performance gains to be made from changing that stock exhaust
 

I recommend you get some Axlebacks. The Borla's are a great choice. I have the Borla catback system (I got it cheaper then the axleback would of cost me) and it sounds GREAT. Here are some clips.

http://www.youtube.com/watch?v=dTOJebdq-kM
http://www.youtube.com/watch?v=i_YL9NruWQQ

~Fred T