I like Castrol 0W-30 better known as German Castrol or GC. It meets BMW LL-01 and is generally thought to be a great oil. I use it anywhere a 30 weight is called for, and I have been using it in my X5. Mobil 1 0W-40 is also always a great choice. Both are readily available, although the Castrol is a little harder to find (Autozone/Pep boys). You can find either on sale quite often.