It'll be really loud and it'll resonate like crazy inside the vehicle.
I installed a pair of Gibson mufflers in place of the resonators and it sounds awesome and along with the AirAid intake system I installed, it made a very noticable and significant improvement in performance.
This is a link to the mufflers at Gibson:
The one I used was the 2.5 inch offset inlet/center outlet. The guy at the muffler shop had no trouble at all (said they fit perfectly) installing.
Sounds awesome when I start it and you can hear the exhaust in the background but it's not annoying at all. When you punch it-man, it sounds awesome!
Did I say awesome?