I've been using 0w-30 for many years and feel it is the best oil made. I used it with a Amsoil bypass system in a 05 V8 4Runner and that oil had over 40,000 miles on it and it was still providing safe protection (UOA verified).
I can tell you the new Toyota 0w-20 synthetic is proving to be a very good oil at half the price.
Hello. I have been viewing some of your posts concerning engine oil. I too consider myself somewhat of an oil enthusiast, and use Amsoil 100% synthetic in both my 2008 ES 350 and my '03 Tacoma pickup. I currently have been using Amsoil 100% 5W-30 in my ES 350 but I am strongly thinking about using Amsoil's Signature Series 0W-30. How satisfied are you with this oil?