I had similar problem with my 400E, my battery drain was also more than 200mA, I found out it was my Becker Radio tuner in the trunk, one IC was short, the tuner never turned off even when the headunit was off, the normal drain should be less than 50mA.
99 BMW 540i 6-speed 110K Km
03 SAAB 9-5 wagon 80K Km
92 400E (Sold) 245K km
Still missing the days with the Benz, it kept me busy.