I removed the muffler and ran a straight pipe on my '06 quad cab. I liked the sound and didn't think it droned in the cab. Recently I wrote the same comment in reply to a similar question and another member said I must be deaf. I do have hearing loss so he might have been correct, it may have droned but I couldn't hear it.
But I'm thinking my '06 had a muffler, a resonator, and a cat converter. I left the cat converter and the resonator in place.
I liked it, your results may vary!