I have the .pdf copy of this D&D adventure, and I am currently DM'ing it (so this is a play-test review). It is for a party of 4-6 PCs taking them from 3rd-7th level.

Pros:
A very good adventure with a unique plot. It is generic enough to fit into any campaign world.
As the adventure states, 'getting there is half the fun', it has lots of very unique locations (like a platform-filled dungeon). It has a 50-50% mix of dungeon locations and outdoor encounter areas, including a small pirate town.
With so many varied locations, almost every character class will shine - and almost every skill could be used with tangible game benefits.

We are currently playing the game and all the encounters seemed balanced. However, the adventure gives 'scaling' options to increase encounter difficulty (nice touch). The adventure also gives generous XP rewards for non-combat encounters and traps (and there are lots of them). There is also many opportunities for roleplaying.

Cons:
The maps are functional, but are lacking by today's standards.
Some minor errors with stat blocks.
The plot has some 'investigation' elements, and the DM may need to re-read the adventure to ensure he/she knows how all the clues piece together.

Overall:
If you want to get away from the usual published adventure plots (you know - save the world from the evil cultists), then this adventure is for you. Unique locations and adventure plot make for some memorable gaming sessions.
With the .pdf weighing-in at 87 pages, it is a real value for your $.