Originally Posted by S-Class Guru

I've owned a '91 300SE since new.
Never saw a more rugged or durable car.
Of course things wear out, but 90% of those are are interchangeable with the 124, or cost about the same.
Lots of room to crawl around under the hood, and inside.
The plus side of the S-class is the obvious timeless design, and it's still a top-line car if it's well maintained.
There are two issues with the 300-engined S-class car, however.
1. This is not a nimble car; it wallows around corners, and you feel the weight always. The 124 will handle and feel like a slot-car by comparison.
But, the S is supposed to be an elegant cruiser.
2. The transmission is geared totally wrong for this car, and just adds to to overall underpowered nature of a small six in a 2-ton car. The poor thing tries to start in 2nd gear, and creates traffic jams at every red light. If you get aggressive, it jumps down into super-low, and nearly breaks your neck.
Then when you get to cruising speed, it has no overdrive, and is screaming at 70 MPH. This eats gas, creates a noisy/busy feel in the cabin, and wears out all the belt-driven accessories. Wish I had tried a 1st gear start kit and lower diffy years ago.

If I had it to do again, I coulda had a V8!
That being said, that little six is bulletproof. Just change the head gasket at 100k, and stay on top of the minor oil leaks, and she will probably run forever (at a zillion RPM).

(And I'll never get rid of her, she's family).

cheers,
DG