For those of you concerned:
I just finished a rigorous reading and re-reading of the main core book. I subjected the book to some moderately rough handling (on purpose - basically I didn't go out of my way to baby it and subjected it to normal use, I dropped it once, accidentally). After all was said and done, there is no visible wear on the book. I know this is a short test, but what I'm trying to say is 'it didn't fall apart'.
The spine appears to be adequately flexible. It lays down on a table open to a page without flipping pages (one side propped on the other books in the set). The cover appears to be resistant to hand oils. I even spilled a few drops of black coffee on one of the pages, it wiped off without stain or wrinkling (I didn't let it sit, the pages are semi-gloss).
There are no visible stresses in the seam. Sometimes, if you favor a page, the book will flip open to that page automatically. That hasn't happened yet.
I have no paper cuts that I am aware of
So far - so good.
My only concern is the lack of smell. There is no 'new book smell'. Something is fishy here...