Thanks for the help and reassurance. And I am sorry for my mistake in subject. I know better.
Just checking my understanding, are you saying all the R350s sold in the US were 4Matic? The reason I am asking is I have seen quite a few ads on FB were there is no 4Matic badge on the back and the sellers describe them as RWD. I've been ignoring those no matter how good condition because I thought they were RWD.