Having played this adventure as a one shot, I can say the following:
There are interesting NPCs with their own different agenda which gives depth to the whole story.
The main antagoninst, Gregorian - has a rich backstory and a smart approach for roleplaying him towards the PCs (good battle tactics as well in the possible case of battling him).
The tower has traps, riddles, skill checks and of course nice encounters - and all these in a one shot adventure!
The secondary antagonist (no spoilers) has also smart battle tactics by game design which sticks well to the overall adventure.
All in all, a good and fast one shot adventure which contains all the elements to make it memorable!
[5 of 5 Stars!]