Truthfully Bob,

It looks very much like a 50-1 plug, synthetic, that's in a very well tuned engine. I've seen a lot of plugs with 25 and 50 hours on them that came out of engines "flow tuned" on a bench that looked almost exactly the same. That engine appears to be running in an rpm range that's above the middle most of the time.

I would be quite happy to see my plugs look that good.