I have a 2001 4.7 liter durango slt and i was wondering which muffler i should go with. I can't decide wheter to get the super 40 (which i hear everybody loves) or should i go with the quiter delta flow 50. I know that both mufflers give different sounds but i was hoping to get something with a deep hollow roar closer to the full size truck. I'm leaning towards the super 40 but considering i have to drive long distances on the highway would i get sick of all the noise? Also for some reason i fell that if i get the super 40 it will give me a crappy sound since i am keeping the cat....i've never heard a durango with flowmaster so help me out....thanks for your time