This is tough, because I enjoy Loren Estleman's work on other Holmes pastiches. However, this is a decidedly mixed anthology. It mixes such a wide variety of styles that it's hard to appreciate them all. The titular novella isn't bad, but the title is a bit misleading, as Holmes fights the Mafia instead of Moriarty's organization (although there's a twist at the end).
All in all, it's not a bad anthology -- I did quite enjoy it -- but $10 might be a bit much knowing that you'll probably only enjoy a handful of the offerings within.