I currently have 96' W210 with over 154,000 miles on it that is my daily driver.
Have had it about 8 years now and it is a pretty reliable car.
It still looks pretty good for an 8 year old car and no one has any idea that it has that many miles on the Odo.

I think alot of the problems that you hear with the W210 are associated with the 98 and up models. These cars have the V6. If you find a 96 or a 97 E320, they have the inline 6 M104 engine it will be pretty reliable.
I haven't had any of the head gasket leaks that were common in the M103 enigines in the W124.
I think this car is a combination of the old reliable tank like technology of the past with alot of the modern technologies of the newer models put in one.

Plan on driving this car until it has to go to the junk yard someday.

Best of luck on your decision.