I've driven both on a few occasions. I liked the slightly firmer suspension on the C class Mercedes.
The E and S class are more pitched at the US market's concept of comfort, and tend to wallow.
Mercedes tend to use soft brake rotors which give you good braking, but that means the rotors tend need to be replaced frequently.
I don't know what BMW do.
I've never been a real fan of either make because of them both being luxury rather than performance cars - apart from special models like the M3 and the AMGs.
I've owned at different times a few Porsches, and I've also driven a few VWs and I've liked them.
My current sports model is an old [1995] Audi S2, and it is the most reliable car I've ever owned, which is why I've kept it.
Audi's tend to be less expensive second-hand, so long as you avoid the dealerships who are now trying to match BMW and Merc second-hand price maintenance policies.
I have heard that while anyone can service a BMW only the dealerships can tell its computer it has been serviced and turn off the warnings.
I know it was so at one time but I'm not sure it is current. [Graeme at Enzo's Auto Service in Frome St can probably tell you.]
[In general, any German car is better than any Italian car - I've had an Alfa and a Maserati!

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