I have had my 95 E320 for 1 year, 4 months, bought it with 82K miles and now have 110K. put 28K in that time (1.8K miles / month or 21K / year average)....
Overall? Very happy, then again most of the things I have had to do to the car, I have ended up like most of us enthusiasts here, seeing as "maintainance" no "repairs" or "cost of upkeep" , or any other variety of words to make it feel better to drive an expensive to maintain car...

, I love the car...
In that time, I had 2-3 problems with fuel relay and ovp(learn to carry a spare ovp and a fuel relay

), and had the water pump replaced 2 months ago ($700 , I think it was)...
Brakes? about $375 per axle to have it done, if you pay someone to do so or have nowhere to do it yourself as myself
Overall, I am happy and love the car and have no intention in ridding myself of this car....first time I looked forward to rolling over 100K miles in a car and look forward to see the miles reach 200K
Get a ppi done b4 you buy it, have a dealer run the vin so you get the service records IN PRINT, if the service was done at any MB dealer, hopefully, as other have said (and was my case) , the wiring harness and evaporator were changed.
Good luck