It definitely is two pieces, I think the main purpose of this was to fully utilize the computer face scanning tech. I think they do the facial features and then worry about the hair. Probably because Luke has so much hair, they made it a separate piece, though I think they could have smoothed that transition instead of their being a clear line between. That's really the only small flaw I see in the figure, but you'd never notice it anywhere but right in front of your face. The figure is amazing to look at!Obviously, since you're using the 5PA Rey. lol
Although I understand why you had to.
I'm not sure I like how the hair is done. Is it a hairpiece separate and attached to the head? Seems like the should have went a different way, as you can see the seem.