Red Line makes the absolute best synthetic oil products available,
period.  If this doesn't convince you nothing will:
http://www.vtr.org/maintain/lubricants-redline.html

If you can't find their products locally (but most FLAPS that have any
interest in performance products will carry it) you can order it
directly from Red Line by the case, which is what I do.  A case of 12
runs around $110-$120 with shipping, and will either let you change the
oil at 50,000 to 75,000 miles without reordering, or you can try to find
someone you can split an order with.

Stuart