Here's the other part of the Peach KitKat review: Yellow Peach. I'll come right out and say it - this is the weaker of the two. They were similar, but there were some nuances that made all the difference.
Based on the picture on the bag, I'm assuming that Yellow Peach was supposed to taste more like the peaches readily available in the United States. This gave me a better idea to what I should compare it.
It smelled similar to the White Peach, but the peach scent might have been stronger in the Yellow Peach. My first bite was good, at least initially. The white chocolate was smooth, sweet, and creamy, but didn't really taste like peach.
The peach flavor kicked in as a weird, sour aftertaste. It wasn't good, and ruined the bar for me. White Peach actually tasted like peach, and the flavor was better. I don't mind eating the Yellow Peach, but they were definitely not impressive.
KitKat Website (Japanese)