It could have been a bad example.
As a car guy who subscribes to 5 car magazines monthly and one weekly for the past ten years, I routinely notice that BMW's have, according to those who test cars, superior chasis / handling / suspension dynamics. The drivers who test cars for the magazines routinely rave about how communicative BMW's are. BMW's seem to win every test.
A buddy of mine just bought a 1995 W124 E420, and put in Eibach springs and Bilstein HD shocks with 17" wheels and it apparently has done wonders for the car.
Check out the posts from Cris or try e-mailing.
My mom has a 1999 E430, and I have a W124, and I prefer the W124 chasis. If just feels like what I expect in a Mercedes.
It may be so hard to find a sportline W210 MB, that you may buy a 92-95 400E / E420 (same engine, same displacement) and do your own suspension modifications.
You may also find that you have expectations that are better answered by BMW's, and there's nothing wrong with that.
2001 E430, Bourdeaux Red, Oyster interior.
1973 280SE 4.5, 170,000 miles. 568 Signal Red, Black MB Tex. "The Red Baron".