The edition shown is basically a reinforced paperback, and my rating reflects Amazon's mistaken identification of this as an Everyman poetry edition -- wrong publisher folks! Do not be misled into thinking this is one of the superior Knopf/Random House Everyman's Library editions.
The lesson here is that if you want a _real_ Everyman edition of a popular title, first check the catalog at [...], search Amazon using the correct ISBN and only then place your order. Caveat emptor.
Unfortunately, Khayyam isn't directly listed in the everyman catalog; it is included in the Pocket Poets series within Persian Poets, ISBN 0375411267