I have used the pressure brake bleeding system at the fleet level and although they do work, they can be difficult to connect, a real mess if you do not get an air tight (brake fluid tight) fit, and they use a lot of brake fluid. I prefer to use a vacuum tool called the Mityvac Vacuum Test Kit that can be used by one person. Instead of connecting to the master cylinder, the connection is at the individual wheel's bleeder valve and the Mityvac vacuums the brake fluid through the master cylinder to that wheel's brakes (drum or disc). The Mityvac eliminates all air in the brake system (master cylinder, wheel cylinder, caliper, lines, etc.) and does a real good job. Also, the Mityvac can be used to check your other vacuum lines/valves for leaks/operation, pressure testing, engine diagnostic tests, etc. Plus, it is a lot cheaper than a pressure brake bleeding system and much more versatile. MercedesShop may sell them, if not then Performance Products sells them for $62.95 plus S&H. You may also want to check your local parts suppliers for availability (I recall buying mine from NAPA). Get the delux kit because it has all the fittings/connectors to take full advantage of the Mityvac's potential. If you buy the Mityvac I suggest you put a bit of grease on the pivot points on the pump to ease operation and avoid excessive wear to the pump.