I did this a few years ago...its only loud when you really get on it. I have since switched back to the original set-up. I'm going to get the Magnaflow cat-back next week.

Take a look on page 2 of my gallery and you will see a pic of what it looked like on the car. I was having trouble uploading it here.

Heres my 1/4 mile with no mufflers:

YouTube - Chrysler Crossfire at 1/4 Mile Track