Oil changes are the key! Many 102 equipeed 190E's have changed hands a few times now, and service gets neglected. That is the downwfall of the M102.
I aquired my two 2.3's with low mileage and kept them up very well. Both my cars went over 400,000kms (about 250K-miles) before requiring any work. Top ends came soon after, but bottom ends were fine. Trannies were weak by that mileage. Very weak!
Odds are that you'll spend way more on ACC/AC repairs, brakes, and electrical odds and ends than you'll spend on the driveline. On a cost/mile basis, the 2.3 is a frugal driveline.
1998 C230 "Black Betty"