Well, you won't be able to hear your car over people laughing if you put one on!
Seriously, I've seen them on trucks and all they do is make them obnoxiously loud and stupid looking. Most of the tail pipe needs to be removed and the "boom tube" (you gota stop shoping at crappy tire man!) is put in it's place. It essentially gives the exhaust a bigger resonating chamber and makes it sound kinda deeper but just mostly louder and stupider. An Intrepid tailpipe is just way too short to make any difference with one of these anyways.
You're pretty much looking at a new exhaust sytem with a performance muffler. There's lots of info and sound clips on this site if you do a search.
but remember this:
The 2.7 is pretty small engine wise, it's only going to sound so deep and throaty. You can make it sound like a rattly ricer exhaust if you want. I was raised on big blocks and staight headers, so my idea of "sounds nice" is probably a little different than yours.
i have a pair of home made mufflers, and my trep sounds like lightening mcqueen on that cartoon cars, but my exhasut is pretty damn short too. its just the headers down pipes and two mufflers. well i say mufflers they arent much more than just echo chambers. obnoxiously loud too. but it turns heads.
yo, I live in Canada. **** that boom tube ****. If you want just a plain nice upgrade change ur muffler. Just go to any muffler shop and get a magnaflow or flowmaster exhaust put on. Its about $150 canadian depending on the model you pick. It will look better and decent sound instead of that redicules loud **** a boom tube does.