I can't attest to the H&R springs as compared to factory sportline springs, but I can offer up some much discussed knowledge.

First of all I have to 300E Factory Sportlines, a '92 and a '93. The springs are shorter, stiffer, and different than regular MB springs. They are progressive. They get stiffer as they are compressed. So the point with shock absorber selection is to match the shock to the spring height and spring rate.

The factory sportline shock is not harsh. It's properly matched to the sportline springs. I replaced the factory shocks on the '92 with Bilstein Sports. They are still not harsh, but they are valved differently than the factory shock. I must say that I prefer the factory sportline shocks as they seem to be less harsh on rough roads. I just can't see tossing the Bilsteins and spending more money on the factory shocks (Sachs I think)

If it were me, I would buy the genuine factory sportline shocks and pay the extra money. Well worth it.

Comfort and HD Bilsteins are designed to a specific working range. Why would you use them on a car with shorter , stiffer springs. Makes no sense to me.

Steve