Mostly price and the fact that you had 8-1/2x11 photobooks from PDF's
Price that did not materialize and no cooperation with PrestoPhoto.
Response from prestophoto.com:
Thanks so much for your order and for your review (:
I was clear in our communications, though this topic can be quite tricky.
To reiterate, each side of a piece of paper is considered a page. What this means is that for each sheet of paper (IE. double-sided paper), it is counted as 2 pages in your project. All printing companies follow the same page count formula, as well as all novels. Think of Harry Potter, the 336 pages in that book translates to 168 sheets of paper to be bound.
I hope this helps to clear up any confusion.