One of the most "rail-free" modules for pfs - as gm you may put amazing roleplay opportunities there - there are enough backstory for npc`s (town and dungeon alike) to make them alive and have motivation. Combats are neat, exploration are neat, layouts are neat. My favorite module.
Just finished this module as 1 lvl character. So... It`s truly deadly. Warehouse is nice trap of mass death (we stepped right in the fire trap and it gone to round 10 and all warehouse on fire and we, choking and can`t do anything,) and last ecounter is even more (we had absolutely no range characters so we leaved it with one dead man). Was running as 4 men party. The most mad scenario i ever played.