If you have weeping around the rear shocks then they need replacing.
And it is 'common' for the rear shock to go on the Brabus....only the Brabus.
BC's aren't bad, but in preference I would go for Bilstien B14's on a standard
Brabus setup. They are ride height adjustable.
BC's 'selling' point is the adjustable 'pillow ball' top mounts, but if one
wants to be technical, then Fast Eddy would be only to willing to tell
you which is the better made/constructed of those 2 makes.
I have BC's on my Brab and KW's on my CDI, and I will be swapping
them over, or maybe even changing from the BC's.