Honestly, I have pretty much nothing negative to say about this book. First, the cover and internal art (not to mention a sturdy binding, which is always nice) are very impressive. It's all evocative of the Fiend Folio and the first Monster Manual, but very obviously not straight imitation of style either. At least 60% of the creatures in the book have a picture to go with them, but none of the art even comes close to being filler, or creating blank white space: the book is crammed with two column, easy to read text patterned after the format of the monster entries in the OSRIC book.
Inside, about 150 new monsters lurk. Some, yes, are reprints from some of the OSRIC modules out there, but if, like me, you have been finding the modules of spotty interest, then this book is a great find. In reading through, I didn't see any monster in there that I wouldn't be happy to use in my home game. I'm on record as saying I'm not a fan of the goofy, but even here, the goofy is understated enough that even the most jaded player will get a kick out of it all.
Right now, my favorite entry would have to be the Avatar of Famine, a semi-undead fellow with a rather unpleasant special ability that makes him more than a match for even a powerful group. Its presence and origin are just creepy enough that they'll fit well in a horror campaign as much as any other.
Another standout is the Fungal Render: a giant, semi-predatory mushroom that has a knack for, well, you can probably guess given the name.
Oak Men fill a nice niche for those of us looking for more fairie folk to throw into the mix.
Of course, there's a very healthy dose of excellent undead, my favorite type of creature in the game, including a new type of elf lich kin.
It looks to me as if the authors looked for a theme for their monsters rather than "just another 1+1HD humanoid." Almost every monster here, as far as I can tell at the moment, fills a new nich (midget creepy tree men) or expands an existing niche into a new field (ritualized self-embalming elves anyone?) and doesn't trample on the toes of older, classic monsters by creating smudged photo-copies so to speak.