All I know that he never would have used other than Shell, Havoline / Delo or Mobil 1 in any of his cars here or US unless its the last can of oil left in world or if ZIC was free.
Nor Ferrari or Porsche ever used ZIC oils.
Its not about Genuine or packed in Pakistan, its about formulation.
A Shell Helix Ultra even Pakistani packed (its imported) can anyday outperform 20W50 oil packed on Mars.
When u make comparision only one is winner and others are losers. Shell Helix Ultra is 2nd to none if u disregard some limited production european engine oils. That is why its used by Scuderia.
Simillarly DELO Gold Ultra is best for various applications one cant even think about. I have used it in a 2C engine, JDM Corolla 2.2 D4D to old 88 Honda Accord & Civic gearbox and iron block A16 engines to lawn movers and a 50kva textile industry generator and it has never let me down.
ZIC is good for fleet cars & cabs where even Rs.100 would make great difference.