In the US market, 0W-20 thin is in. In Europe, 0W-40 is the standard bearer. But you'll find the same car spec'd for either oil depending on the country where it sells. To simplify, I believe I could use Castrol Edge 0W-30 in everything, whether it's a Toyota, Mazda, or BMW (not the Z4M). GC is looking like the universal motor oil for my fleet.