Another thing to consider is the "Sportline" option. This was available from the factory on your car as an option. It included stiffer springs and shocks, wider eight hole alloys, wider tires, quicker steering, more supportive seats and a smaller diameter steering wheel. The car is also a little lower.
You can buy any or all of these parts for your car. It would be a good way to keep it all MB and use parts that are specifically engineered for your car. You wouldn't sacrifice ride quality for extra performance or run the risk of ruining your car by gambling on aftermarket parts that really don't meet MB standards.