This is SO COOL!
A great way to introduce a little Weird West to SnS (or other western games, if you work it a bit). This supplement allows you to play a small posse who are akin to the Men in Black, fighting demons and such that the common folk refuse to believe are real. It's a great way to add just a touch of weird west without it becoming overwhelming. (or it could, if you want).
Again, Dave's deft touch of using familiar tropes well but innovately so it doesn't feel cliche.
in 5 words or less: GET THIS