I have the exact same car and I experience the exact same thing (started about 3 kmi miles ago) and it has 98 kmi miles now.
Mike: The 1991 300E has the single cam (M103 motor).
Mine is also a bit wet around the front timing cover/head gasket area but there is no drop. Mine does have the belly pan so if there is a drip, I should see it on the garage floor.
I see higher oil consumption if I drive at high speed for hours. Normal city and occasional highway driving does not use oil.
Until July, 2001, I also owned a 1990 300E (same engine). Like the 91, that one has some wet area around the front timing cover/head gasket area but it drops one or two drops every day. When I sold that car with 120 kmi on it, it does not consume any oil.