Review (17 March 2019): Today I ran Chapter 1 of this supplement for a party of four adventurers: 4th level Bard, 3rd level Ranger, 2nd level Cleric and 1st level Paladin. The ability check DCs and combats were adjusted to fit the party strength.
I initially chose to run this supplement instead of the standard Waterdeep: Dragon Heist chapter because I felt that the players may have either read or played it before. This turned out not to be a factor, and the real reason for running it was that I enjoyed the whole concept and theme that this supplement presents. In the previous week, I ran Blue Alley, and this provides the opportunity for continuity in the location setting.
I had the party engage with Mirt, the NPC from Blue Alley, who gave them a side quest to get them started. It is while they were engaged in this side quest that they began the first encounter. The party managed to thwart their opponents peacefully and send them on their way (only to have them turn up again later!). The stake-out was in fact interrupted by the returning foes. The party were very blind to spotting anything, but very cunning and fortunate in their battle with the kidnappers (including strong ranged attacks on the flying opponents), and ended up saving their target from capture. A clever set-up for their stake-out provided useful strategy to control the battle. Planning a staged combat is fun for the players, and the unknown factor adds an edge to the tension.
The party were full of anguish trying to piece together the clues and they dreaded finding out what would happen next (I emphasised the drama and the threats of the unknown), but as they headed to the next location after a significant and successful battle and armed with more clues from the main NPC, they were full of confidence and sailed through the rest of the adventure with great enjoyment. The whole setting of the lair was so amazingly inspirational, and as a DM, its a lot of fun. The players enjoyed the conclusion, and finished in high spirits in just over four hours. The challenge at the beginning as they tried to figure things out makes the successful adventure all the more enjoyable.
My advice to DMs is to keep referring to the hardcover alongside this supplement as there is a lot of material relevant to Chapter 1 in the book, and the supplement can't be run without the book. As I haven't run the hardcover version yet, I can't really compare them, but if I have a chance to run this again, I would use the supplement as I enjoyed it so much.