if you want a quite exhaust I would recommend an Rs*r exmag. I'm obsessed with these things. They are really quite except for a slight exhaust tone, similar to what the exhaust on a new eclipse gives off. And at wide open throttle at a high rpm they make a sweet exhaust tone. I've never heard a better exhaust, nothing ricey or high pitched.

On the downside they are a little pricey though. Modacar.com sells them for about 500 bucks.