The user name is
Bora and I found
the thread that refers to an X1 sDrive 20d M sport with BMW Performance brakes installed.
Unfortunately most of the pictures are dead links and the direct link to
Bora's personal web site now generates a 404 error.
I found a single photo in another thread, a close up of the wheel and front brakes.
Good news though,
Bora was active today! I'm going to send a PM.