The Mercedes-Benz is a wonderful car that is designed to keep sound outside the vehicle. Putting any kind of subwoofer in the trunk that fires into the trunk only emphasizes Mercedes' engineering. The trunk lid flexes and the punks on the sidewalk say, 'Way cool!'. If this is your goal, put such a subwoofer in your trunk. If you want the bass to play inside your car you must have a subwoofer enclosure that has a partially external port that can exit from the top of the box and rise through the heavy steel package shelf under a grille. The bass will have the same quality as your Mercedes! You will need an amplifier dedicated to driving the subwoofer with a four channel amplifier driving the four corner speakers. Do not retain the paper-faced, o.e. speakers, but replace with same size coaxial speakers. All aftermarket Aisian coaxial speakers are similar sounding and differ mainly in efficiency. MB Quart, JL Audio, Dynaudio, Focal, and Morel make better speakers but they may not all fit in factory locations. MB Quart coaxials will fit and sound much better than stock speakers. P.