Here's the list of approved oils for our engine.
MB 229.5 - Multigrade engine oils (Specification 229.5) - Mercedes-Benz Specifications for Operating Fluids
If you prefer the 229.3 spec you can find it there too.
These are oils the MB says meet their requirements for our engine. I'd stick to one on the list even if you have a desire to be different. Our engine will run with just about anything in the crankcase as will most engines. They are lubricants after all. I just can't find a good reason to change. Perhaps other oils are better but Mobil 1 0w-40 has proven to be more than "good enough" IMO.

Les