If I could get German Castrol here in Germany, I would (irony). It's only sold in Autozones, sold as a a 0W-30 (but is a heavy 30 grade), and doesn't conform to the gay SM industry standard. Damn good oil for non-racecarz and has been a benchmark for synthetic oils for years.
Make sure it has a red label and Made in Germany on the back (I think the regular garbage syntec/edge is exported from brazil).
For now, I run Mobil-1 5W-40 Turbo Diesel oil. I'll definitely run GC again when I get back to the States.