Congrats for your new Benz and welcome to the forum.;
Vettes: I have owned Vettes since 1971 (it was a 1966 327/350 then) and still own and enjoy a 1978. A 1967 Vette (427/400) was a drag quuen (king?) while my 1984 was a pure dog.
back to the Benz: The W124 serie has been widely recognized as being one of the greatest product Mercedes ever built.
OIL: Stick with Mercedes recommendations. Do not try to outsmart the engine builder by using a product and grade not approved by Mercedes, That's one of the secrets for their longevity. Do not exceed the prescribed oil change intervals, whatever oil you use.
And pls. don,t start an other oil topic. We,ve seen so many and I think everything has been said (at least 10 times)
I suggest you make a search and see
Good lucj with your new wheels.