In examining the surfaces of the bearings pulled from my 09 at 109K miles, there were variable amounts of wear between the different cylinders. This variation may have several different causes: crank deflection, block alignment, rod deflection, ... (I really don't know, but my point is that there could be multiple causes.)
Bearings with isolated spots seemed to have "pull out" that is an abrupt change between the two different surfaces. In the OP's pics similar to areas on the bottom halves of several cylinders. If one refers to Clevites' failure guide, it may indicate surface fatigue. This may be why BMW switched bearing types.
http://www.wilmink.nl/Clevite/Clevit..._tech_info.pdf
Although there have been many pictures of worn bearings, there has not been a detailed failure analysis of the surfaces. Neither has there been any finite element modeling published of the S65/S85 rod bearings. From what I could glean from published literature of a generic rod/crank system, the stiffness of the rod also plays a role. I'm sure BMW has done this as well as their suppliers. However as nobody will ever admit to an error, I doubt that they will be made public.
I'm not sure what is considered an expected motor life, 150K, 200K or longer. Conversely some race motors are expected to have considerably shorter lives. My hope is that changing the rod bearings will extend the life to ~200K.
One additional wrench go throw in. Do the Germans still have beer dispensing machines in their factories?
