Bilstein B4 Shocks: How Long Do They Last?

Hi,

Since I'm currently investigating various issues related to my specific model/variant:

How long did the shock absorbers last for you?

My Bilstein B4 shock absorbers (standard gas pressure) are almost 100,000 km old.
The road handling, especially in the rear, is terrible. But what's the reason for this?

Should I replace the wheel bearing housings (those 4 rubber and metal parts) first?

m;