A few hundred more on the dyno. Plus another 900 miles this weekend. Idle pressure holding steady at 15 psig!!! You guys do what ya want! F the synthetic!!! 
Hoist! 
If you don't run really hot and you change at reasonable intervals - there is probably negligible difference - BUT if you get hot one day your dino oil is going to trashed.
I can only say that my dad was in the high performance lubrication field for racing and construction for most of his adult life after leaving the USMC - and he swore by synthetic. There were few folks with as much experience, like real on the job site and at the race track. He was reading industry rags right up until he died...and when I was there this past spring to visit him folks were calling him with questions about lubrication for their vehicles.
Your MC - do whatcha want. I'll run synthetic.
Sean