I bought mine 1 year ago and have put 20k on the car with no worries. It had 152k at time of purchase. This is my fifth older mbz and is my favorite one of them all.
Fun to drive, great reliability and the interior layout is practical.
I have seen the 3.0 liter inline six go 400k plus with just a top end rebuild.
Things to be aware of: head gasket and engine harness failure.
A small … price to pay in overall upkeep, for a car that is safe, has classic lines and can handle high mileage with proper care.