Emmy,
I took the following from my alldata subscription for my 560:

Nominal Thickness
Front 1.102 in
Rear 394 in

Minimum Refinish Thickness
Front 1.024 in
Rear 0.339 in

Lateral Run-Out
Front 0.0047 in Note: Maximum
Rear 0.0047 in Note: Maximum

The above is a copy-paste from the specifications table. I also found 2 threads here with posts by RKreutzer who refers to a beginning thickness of 28 mm (1.1 inches) with a service life to 25.4 mm. Equates to 1.3 mm of wear per side, or not a whole lot. Not accurate, but i think that is about the thickness of a penny for a lip. Kreutzer was referring to a 420 sel. Do a search for "brake rotor thickness" and only 5 or 6 threads will come up, he does some good posting on 2 of them.

Hope this helps

__________________
Earl McLain
'02 C230 Kompressor
'89 560 SEL "Frau BlueCar" (retired April 2004)