I was a bit leery of picking this up due to bad reviews, but the price was very appealing (128 pages for $14.95). Overall, I'm glad I picked it up, although I paid even less than it's low cover price (thanks to a game store on Ebay).
Essentially, this book details the 'Mystic Warrior'. Mystic Warriors are basically just orders or organizations that have learned to fight using magical abilities. Essentially, a Mystic Warrior is a broad type of prestige class. It's set in Mystic Eye Games own campaign setting, but is relatively easy to adapt to any. For instance, the Templars, Thugees, and the Assassins of historical earth could possibly be "Mystic Warriors" (and in fact seem to be the inspiration for some of the groups in the book).
The magic abilities are generally based around what is called 'Vitus'. Essentially, 'Vitus' is just a way of saying 'Spell Point'. Characters get so many vitus (spell) points (based on level, class, and their stats), and can spend them to use magic powers called 'techniques'.
Some magic powers to specific to certain mystical orders, but some are common to all. The latter are learned almost like spells are. By my count, there are 22 different mystical orders, each with their own prestige class, and 52 techniques. So there's a lot of material in here. Some of the orders are more suited for villains, while some are PC orientated.
Each order and prestige class gets a good 4-6 page devoted to it, including a full description of the class, the order, as well as how to adapt it to another fantasy setting, art depicting what members of that order looks like, their symbol, and a short piece of flavor fiction. The orders range from the very interesting and cool to the goofy (the wolf people) and somewhat lame (people who become golems). But the majority are good.
This product actually reminds me a lot of the old "Compleat Whatzit" books from Bard Games. Decent but somewhat amateurish artwork, odd writing at times, but essentially a labor of love. So it's hard for me not to like this a lot.