Recently purchased from the local game store. Best buy in a few years, honestly. Quality book, sturdy, great art, and tons of new monster possibilities. A must have for anyone who enjoys custom/unique creatures
I'm pretty happy with the amount of content this book offers; there are plenty of new options for all classes, the 'new hybrid classes' are somewhat exciting, and there is a bit of slightly useful info on writing up new classes, archetypes, and PrC's...
That being said, I consider myself fortunate to have only purchased the pdf. The great number of errors, clunky wording, and poor organization of the book tears my rating down to 2 stars. The classes are either poorly constructed hybrids of old classes, polished up versions of old ideas, or easily broken. Most of the archetypes for old classes are interesting, though the ATs for the new classes are underwhelming and typically underperform compared to the base class. We'll be using it in my games, though there will be some home-brew fixes and alterations.
Wait to buy a hard copy until it gets a good edit.