http://www.mobiloil.com/USA-English/...uck_5W-40.aspx
Notice that this is one of the only ones that Mobil will still tout as "Fully Synthetic".
Also - check out bobistheoilguy.com. There is a TON of good reading on there regarding all sorts of oil and associated tests. The information from this site is the reason I went to M1 TDT.
The Lotus and Ferrari guys adore this oil, if that tells you anything. With Amsoil being over $9/qt now, this is the way to go.