Mercedes is telling what want,
Go to reviews of oils and you see how is.
Mobile can last in perfect condition for 6000mil
Amsoil can for 25000 or 35000 mil
I am with Amsoil for over 20 years and my engines are in original condition, never open.
My 190D very high mil and 260E.
ML320E 150 000 mil.
This is not my opinion, you can see all tests how Amsoil is.
Mobile is nothing special.
You can see all on the net. Just you need a time and read all.
I own brand new in 1982 300D Turbo - I believe to Mercedes Service All oil changes was done by MB.
in 45000 mil was replaced 3 x Turbo.
I sold that car and get new 1984 190D.
From the beginning I start use Amsoil - I have lots of problem with Autotransmision.
When I come to dealer for repair of transmission –MB wants change engine. Oil.
When I tell I use Amsoil - synthetic - want take my warranty a way.
I call head office, talk to German Eng.from that time was o.K. No body make problems for me more. Today my 190D 750 000 mil.
Today engines are more sophisticated. need good lubricant.
Why so many engines failures. Who used regular oils?
Look how many quarts of oil are in the engine. If use 4Q only can last for 2000 mil.
This all is proven - I don’t promote Amsoil - look on German oils if you can get.
Are best. North Am. is a big business and every body need make some money.
Mechanic too.

Best Regards.