I loved my Benz for the firs 150K miles, then I started to have trouble with it. One thing after another. First the wipers had to be replaced, then the floor mats and then the air pressure in the spare needed to checked. I don't know if I'll ever buy another.(/s)
I've had several..what I really miss on my 230SL was the ability to do most of the basic mechanical work myself...with a decent set of tools and a timing light....all I needed..Now, I need a computer just to open the hood..
When I was a youngster I recieved a old Mercedes 300TD (W123) from my father. Since I am a quite skilled mechanic I managed to drive this car up to 495.000 km (I think something about 310.000 miles - but I am not sure) and sold it then for 5.000,- Deutschmarks . :-)
But you are right - the later models weren't that massive anymore. After 300.000 kilometers most of our Mercedes were toasted. Anyway in the moment we still use a 230 SLK with 250.000 km (something around 156.000 miles - but still not sure) and the car still works perfectly.
I had the same problem with my 190 Benz. Bought it with 52,000 miles on it and now has 257,000. Still going strong. I'd consider buying another but they pretty much only come with automatic transmissions.