Hi all, I just received the oil sample results from Blackstone Labs on my wifes C230 yesterday and the Mobil 1 did an excellent job. I can't attach the .pdf here so I'll just type in the results. A little background on this sample, Mobil 1 0W-40, with 4950 miles on it, I use a STP oil filter and a K&N air filter. Her car now has 60k miles on it.

Aluminum 2
Chromium 0
Iron 5
Copper 4
Lead 1
Tin 0
Moly 66
Nickel 0
Manganese 0
Silver 0
Titanium 0
Potassium 0
Boron 134
Silicon 3
Sodium 5
Calcium 2537
Magnesium 20
Phos 743
Zinc 876
Barium 0

TBN 5.8
SUS Vis @ 210'F 65.9
Flashpoint 360
Fuel .8%
Insolubles .3%

Here are the comments from Blackstone Labs:

DALE: The universal averages column shows typical wear from this type of engine after about 4000
miles on the oil. Your oil was run 4950 miles, and wear levels read well below those averages. We
did find a little bit of fuel dilution, which is common in engines that see a lot of city driving and/or
idling. We don't consider it a problem until it reads above 2.0%. The TBN read 5.8, so this oil had
plenty of active additive remaining when you changed it out. The oil could have gone longer, and your
engine can take it, too! Try 5500 miles next time.

I also sent in a sample of the ATF for this car as well, if anyone would like to see those results posted here let me know.