Royal Purple

I just got through putting Royal Purple synthetic 10w40 in my 73 318 Duster with 80,000 miles on the motor. I have driven 500 miles since, with no additional leaks at all. Its still runnin good. I figured it has the additives needed to keep my flat tappet Comp 260 cam (.440 lift) healthy. It has 2000 miles since it was added. Do you feel this is a good oil? Little expensive, but maybe worth it. Anyone else running it or have had experiences? -Justin