What was the first year MB used the M104 engine in the W124 Chassis? Was it '93?

What was the last year of the W124 chassis?

How does it compare to the M103 in power, reliability and longevity?

Any problems inherent in the early model years of the M104 (not just the engine, but the car in general)?

What octane gas is recommended for the M104?

I'm trying to decide between an 92 300E and a 93 to 95 model.

Thanks