I've been in the graphics industry for 25 years and have worked with a number of printing companies in that time. I've never had an issue like I had with Zoo Printing. First they changed our graphics files without telling us. Second, the quality in the printing is just poor. The trim actually cut off some typography at the bottom of the page. (I've done this enough to know what is acceptable and what isn't. This is just poor workmanship, any two-bit printer in the world could do a better job than this.)
But the worst problem of all is their customer service. They don't return emails to their site. Three different times they said that they would have someone return our calls, but never did. It is pretty obvious that their way of handing a problem is to give you the runaround until you give up. They're extremely rude.
Never use Zoo Printing.