Commenters distinguish the thicker, firmer top-grain leather of early and mid cars (through 1997) from the softer leather of 1998-1999 cars, which looks the same but is felt to wear worse long term. Owners defend the material as genuinely high-quality versus modern thin or synthetic hides, and note it hardens with age but softens again with conditioning; re-dyed interiors are treated as a red flag.
Interior leather quality declined in later years
Mercedes-Benz S-Class (W140) · cosmetic