The Kerker muffler was a lot quieter since it is well baffled, mine sounded very smooth up until 6000 rpm, when it started to roar; the DCC reverse cone is little baffled, not too loud up to 3000 rpm, give it more gas and it really roars, I´m sure the whole neighborhood will notice you are arround, kind of like comparing silk with sand paper.
I will say, with the Kerker muffler is more of a street pipe sound, and with the DCC reverse cone you will have a race pipe sound.