The logic that drives these AI objects is impressive in its simplicity. I tend to over-engineer when I create AI. These are great examples of how to create simple but effective platformer enemies. The art that it comes with is nice too, even though I'm not planning to use it - it's handy for prototyping. Easily worth the full price, imo, and a total steal on sale.
My only complaint is the music, which is super-loud and can't be disabled in the game itself. I'd suggest deleting the music audio before launching the examples, or at least silencing it, because it's quite annoying as-is.
TLDR: If you're making classic platformer enemies, this pack is well worth it.