Hi there, I've read most stories on the 5W20-topic. It seems, the reason is CAFE, not engine care. After all, I need to do first oil-change on my '03 Accord V6, which "requires" 5W20. I've never tried a synthetic oil, but I feel I want to go for it. Also, read about Amsoil oils. But, I'm wondering, if Amsoil is so good, why aren't these sold in the auto-parts shops? ***Bottom line - please, advice which synthetic oil I should go for (or should I)? Is it going to be Mobil 1-5W30? I checked with local dealers - they offer Valvoline and Castrol. Keep in mind, I live in SoCal Desert, with summer temp. 100'+F.