I'm going to be getting a new muffler soon. My question would be on the flowmasters since I can get that fairly cheap what series muffler would I want to go with for the loudest and deepest sound. Going to be staying with the one muffler setup with duel in and duel out. My question is would the 40 or 50 series be the best way to go to get the sound I'm looking for? Also would changing the muffler do that much more or would I benefit that much more from changing the full cat-back? Also I will probably be taking the cats off if that matters and will that affect the performance negativly?