0w30

Mobil 1 Fully Synthetic 0W-30 What is every one's take on the 0W-20 or 0W-30 fully synthetic oil? Do you think it is worth the hype and would you use it in your Genesis? I was in Wal-Mart today and it was $22 for 5qt. Even though this car calls for 5W-20, 0W-30 according to Amsoil protects...