+1 on breaking in with conventional oils.
Over the holidays as all the men were standing around the barbque pit watching the smoke rise and going "ooohhhhhh!" as the lid was raised.
My nephew talked about oil efficiencies and this is my take on it.
He is head engineer at a power plant. They are in the business of making money by selling electricity. Coal fired power plants are only around 30% efficient. Anything to raise that efficiency or increase the life of equipment means more money for the company.
He gave an example of switching a big generator to their current syn oil. They had a 3% increase in efficiency and lower temperatures. These are cold blooded engineers measuring and testing and computing results. They TEST every thing. Bearing wear, independent oil analysis, temperature, and things I don't even remember. (We were drinking beer and watching barbque!

)
They now run industrial grade full syn in all the plant machinery (generators, turbines, left handed widgets). They run automotive grade full syn in plant vehicles (cars, trucks, bulldozers). No motorcycles!
The plant engineers said, and the accountants agreed it was wise to switch.
He now runs full syn in his personal vehicles (some vintage).
That's why I'm keen to try the syn oils.
I'm going to try it in the rebuilt 750.
I'll keep the 360 on Rotella as it run's great and needs no engine work.