This one-shot delivers on its promise: "go shoot zombies!"
Full disclosure: I ran this as a home-game with custom PCs, so I'm not sure how the experience of the all-gunslinger pregen party would differ.
My minor quibbles are that the final encounter (especially if enemies' tactics are followed exactly as written) is underwhelming difficulty-wise and there isn't really an option for the players to discover more about the villain's motivation unless the villain monologues. Added clues that the players could find and then perhaps even use in the final encounter would've been neat.
Additionally, the tension would have been improved by having an additional complication when exploring the various buildings: e.g., NPC in danger.
This scenario is fine (2.5 or 3 stars) for veteran players & GMs, but would be terrible as an introduction to PF2e.
The library research section is a bit long, somewhat ending up as a "roll dice repeatedly until you achieve enough successes" activity. Additionally, the scenario is set up so that the PCs can learn something that would be helpful for facing a certain enemy...but only after they've had a combat against those enemies.
There are too many enemies with a large number of and overlapping immunities, making certain PCs near-useless in multiple fights.
All that said, the final encounter was fun and the middle of the scenario provided nice opportunities for roleplay. The lore is tantalizing, and should provide a good payoff in later metaplot scenarios. The NPCs' personalities, quirks, and motivations were well-described and distinct.
