Generally, full synthetic is better than a synthetic blend, so PP synthetic is likely better than the synthetic blends of Mobil Clean 7500 and Motorcraft. However, from Mobil's website:
"Q: Do these oils affect car warranties? If an owner’s manual recommends oil changes at 4,000 miles, will the car warranty still be in effect if I use Mobil Clean 7500?
A: Since the Mobil High Endurance Motor Oils exceed industry and car builder requirements, drivers can rest assured that their engine is well protected. As long as drivers follow the oil-change-interval guidelines set forth in their owner’s manuals, they won’t have to worry about voiding their warranties.
ExxonMobil stands behind the performance of its products. Per the guarantee listed on the back of the bottle, if a vehicle should suffer a lubricant-related problem while using Mobil Clean 7500, we will provide reimbursement for required repairs."
PP is only warranted for 4,000 miles/4 months and only covers 15 parts per their website.
I don't see that MotorCraft Oil has a warranty.
So since you plan to run 7500 mile OCI, I'd pick the Mobil Clean. Of course, there are better oils available with better warranties for longer OCI's.