IMHO the ideal price point for X would be:
• $999 256GB
• $1149 512GB
Forget the 64GB altogether.
Interesting to see Apple now only offer the 7 and 7 Plus maxed out at 128GB - no more 256.
Maybe they need those 256 yields for the 8/X?
it is not about yield .. it is about demand , 256GB is very expensive and when you pay that much you will choose the 8 over 7 granted ...