So, for my last (first) oil change I was looking for 0W-20 and could only find it in Mobil1 and Castrol Edge Titanium. Mobil1 and Subaru engines have had a rocky history so I won't us it. I've used Castrol Edge in the past, but apparently this new "Titanium" formulation is not as good as the old version. Castrol won't release HTHS numbers for their US products. So that's off my list now too.
What I ended up going with was Pennzoil Platinum 5w-20. The BobIsTheOilGuy.com forums really like Pennzoil products, and short of expensive high-end oil (Redline, Amsoil, Motul, etc) they have some of the best product. Now, we're seeing really high temps this summer, so the higher start weight doesn't concern me. But I would like a recommended 0w-20 for the winter. Pennzoil makes a Platinum 0w-20 (but not Ultra) however I only found one nearby source for it.
Wal-Mart.
I dislike giving them my business, but I may not have an option once the temperature begins to drop.