If you change the oil regularly, the chain could be fine to well over 200K.
I had mine changed at 205K just for precaution, but it probably wasn't really necessary.

However, at that mileage, assuming some of these things haven't already been replaced, you will be starting to have issues like tensioner, radiator, alternator brushes, maybe A/C compressor, water pump, head gasket leak, etc. etc. etc.

Not trying to scare you, but that has been my experience on two different
300E's both bought at around 100K.

Steve
92 300E Sportline 231K