w210 frt suspension repair question

[apb]

My 97 e420 has 62kmi.
I had it to the dealer twice for slack in the steering. They replaced both front control arm bushings the first time - it was only 50% better.
Brought it back to another service team. They had to redo the bushings (said they were incorrectly installed) and replaced one of the ball joints.
The car is still not perfect. Especially on rough surfaces and bumps the car wants to sort of do its own thing, forcing the steering.
Any thoughts what else it could be. It is 80% but not perfect - the dealer got on my nerves and I will be going to an independent (another reason to buy 3rd party extended warranties).

[mbdoc]

If the steering IS loose then the tie rods & ends should be checked. However if the steering is tight & the front end feels loose then the shocks OR the upper control arms may be the problem.

[apb]

Should I expect a good independent to have problems diagnosing the problem? In other words, are W210 suspension problems particularly tricky to figure out.

[apb]

Latest update!
Seems like the idiots at the dealership - thank you MBUSA - managed to misaligned the car. An independent shop redid the alignment to fix the problem.

[haasman]

Also, as with the 124 and 210 cars, rear suspenion problems can make the car handle weird. Be sure to check the rear links as well.

Haasman