FIST is A-Team meets SCP (or alternately Clive Barker's Jericho meets Full Metal Panic,) and I am strongly recommending it on that premise alone. It's twelve pages but packs a decent crunch, and while it runs on PBtA, I think this is one of those cases where it's going to appeal equally to PBtA and non-PBtA fans due to the way it handles combat. So if you're used to OSR or Delta Green or Night's Black Agents, there's still meaningful weapon damage, armor, and HP.
In a typical game of FIST, you play as an elite team acting primarily under your own authority and contending with weird forces. Those weird forces might be a recently unfrozen yeti monarch looking to bring endless winter down upon the world, or they might be a government agency that has become infested with symbiotic bees.
The book itself has a zine feel, but it's a very high quality one. The layout is excellent, and it manages to have a sort of military handbook tone to the art and also to the way the text is arranged on the page. This is really cool and it contributes a bunch to immersion.
There's also a lot of neat elements here that are admittedly small, but really welcome, and that I would not mind seeing standardized. For example, the table of contents is split into PLAYERS, REFEREE, and SUPPLIES sections, meaning the book is not only easy to navigate, but it flows really well. The GMing advice is also really straightforward and good, and emphasizes both challenging the players and supporting them.
Possibly my favorite thing in the book is the Traits system, which is the backbone of character creation. Each Trait includes an item, a stat mod, and a thing that you can just do (rip open doors, disguise yourself flawlessly, fast talk enemies, etc). To build your character, you pick two. To level up your character, you pick another. It feels extremely smooth and custom, and it makes character creation a matter of seconds, rather than minutes.
Overall, I would recommend this to anyone who likes pick-up-and-play crunchy games themed around espionage and the supernatural.
Honestly, I'd love to buy (or write?) a mission pack for FIST, and I'd be intrigued to see more of the setting.