rack & pinion inherently has less play than recirculating-ball, and hence feels more precise.

recirculating-ball however, is more resistant to kickback, i believe.

German cars are known to have that dead spot on-center (i.e., when the wheels are pointing forwards), as a feature for high-speed cruising stability, so the car is not overly sensitive to small steering wheel movements in the straight-ahead position. Probably the early W210s were too sensitive in the on-center position, making the car react too much to small movements of the wheel at speed. Some car magazines call this dead-spot some sort of autobahn "sneeze protection" - imagine crusing at 130mph with the wheel too sensitive and you sneeze, and inevitably move the wheel ...

there are many other factors that affect the steering feel of a car: caster, camber, steering axis location & steering offset (i.e. the location of the steering axis on the road, vs the center of the tire patch), weight distribution, even choice of tire. Even aerodynamics, in the case where the change in downforce varies greatly with speed.

there was an article in R&T or C&Driver about 2yrs ago on the steering mechanism of the BMW M3, and why it was considered the benchmark in steering feel. Very interesting read for the technically-inclined ...