I will start off by saying that I took time away to methodically consider my review for this, and am giving it a higher rating than I had initially wanted to. And that is because of miscommunication and misinterpretation of the item specifically stating "Note: This product contains compiled information from Bags of Tricks, Figurines of Wondrous Power, Horns of Valhalla, Robes of Summoning, Robes of Useful Items and Rods of Wonder. If you own some or all of these products, Wondrous Treasures may not be for you!" This not the case. I have Robes and Figurines. What's in there is not in here. So, go ahead and by those too if you'd like to. I bought this expecting this to a compendium of all the above books. This is not the case at all. I wish that had been made more apparent.
With that out of the way, lets do the actual review.
The pdf is 29 pages in length with 20 pages of content. It's main goal appears to make note how many times an item has been random chosen and how many times a specific ability has been used on each item. As well, it lists the identify DC, magic aura, how to activate and use, specific construction prereqs, and how to destroy it. Finally, it gives the reader the stats of each creature that you can pull from each item (cat, bat, boar, giant owl, etc) so that it's not necessary to search through the bestiaries, or do up the stats with the template (ie. for the Robe of Bones and the skeleton undead template). In some cases, there's even a blip on the item's lore. With regards to animals, a chart is also listed for how Handle Animal can be made use of during combat with these creatures.
Overall, if you're looking for a supplement for the specific wondrous items listed in this pdf, and need a quick and easy reference so you're not forced to do all the homework yourself, this is the book for you. All the research and box charts have already been done for you. As a GM, I can appreciate the convenience.