I can't speak to the Durango, but on my Magnum I just removed the suitcase and left the resonators. The resonators are there to eliminate the drone caused by the MDS system running, so without them it will be bad (there are ways to get around this, you can turn off the MDS with a tuner, or physically go in and delete it). Just taking the suitcase out made my car sound great! It's not terribly loud normally (my wife riding in the car on the freeway had no problems with it, and we were able to hold a conversation without issue) but when you stomp on it it roars like a muscle car should.
1949 International KB2, 302/T5
1968 Dodge Dart GTS, 340/727
2006 Dodge Magnum R/T "SRT Design"
2016 Dodge Durango Limited