The 2.5 turbo, I'd imagine, would be similar in passing power to the E300. If all figures are correct.

121 bhp @ 4600 rpm 165 lb/ft @ 2400 rpm(2.5T)
136 bhp @ 5000 rpm 155 lb/ft @ 2600 rpm(3.0NA) weight is similar

It's really hard to tell. I don't have the dyno charts in front of me. I suppose it depends on how well the car was serviced. Of course that is most usually always the case regardless.

BTW, if you ever plan on juicing out some power, then the 2.5 turbo is your best bet. However the '93 300D has an ECU that requires that new fangled techno crap "chipping". I'd much rather prefer a wooden-edged screwdriver instead of a circuit board, myself.