the 300e owner's manual sez:
"The oil pressure at idle speed may drop to 0.3 bar (4.4psi) if the engine is at operating temperature. This will not jeopardize its operational reliability.
Pressure must, however, rise immediately upon acceleration"
you've got lots of margin there ...
i also admit to be overly sensitive about and watchful over the oil pressure gage readings of my M103 190e2.6 ...