This product is absolutely horrible. First off, the product description and the information in the DriveThruRPG system is just plain wrong. The information in the system lists the product as 4E/GSL, but the cover shows the Pathfinder compatible logo. Neither of these is correct, as it is written for D&D 3.5.
The product claims 60 levels for the tower, but it is actually only 15, with 45 more exact duplicates of each level, with the only change being a decimal place in the level number (ie, level 15, level 15.1, level 15.2, and level 15.3 are all identical). There are 63 PDF files in this package, all rather small. It would have been much more convenient if the publisher had simple created one large PDF file with bookmarks.
The maps themselves are rather obviously created by an online random dungeon generator. As such, they have no semblance of actual design, and the connections between levels do not line up at all.
The writeups of each room also seem to have been randomly generated, and once again this shows as a remarkable failure. Apparently silver and red dragons share the same dungeon level peacefully. There is also not even the remotest inklings of a storyline.
The layout is another failure on the part of this product. I'd imagine that it is unchanged from the random generator, it certainly appears like no attempt was made to improve it. Sometimes the end of a page even slices a line of text in half horizontally. Exceedingly sloppy work on the layout front.
Bottom line: There are far, FAR better products available for this price than Tower of Terror. In fact, I would say there are far, FAR better FREE products out there than this one. I don't know much about Art of War Games, but I do know that I will never consider another one of their products again after taking a chance on this and Lawbrech City (which shares almost all of the same problems).