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In my understanding RCS is a thicker and high SAPS brother of RUP
(mid SAPS, it comes with BMW LL-04, MB 229.51, formerly VW 511 00,
Porsche C40 and A40 before).
I use to run RCS on my old 930 (no daily of course) for several years.
OC every two years, way below 5000 mls.
That said, I'll...