Anthologies are ever a mixed bag. Rarely will a reader love every single story, and, in this case, I didn't even like most of them. However, I can give this anthology some higher praise than some where I liked more of the stories: it's more consistent. The stories are all easy to read and fast-paced. Generally, there's at least one story that's like pulling teeth to get through, but, even the ones I didn't like, moved right along and kept me entertained. Marr and Armstrong's anthology keeps the reader engaged and moving forward.
Shards & Ashes is a very easy read, and considers a wide variety of dystopian/post-apocalyptic scenarios. If you're a reader who usually avoids dystopian stories because you don't like science fiction, this might be more up your alley, since most of them are more fantasy-based.
What Left Me Wanting More:
The downside of a lot of these stories was the focus on romance. In a short story, there's just not enough time for world building and setting up a convincing romance, and I think that in a post-apocalyptic anthology, the world building should be the first qualification. Romance can be present, but it should be added in later, not the central focus. Obviously, a couple stories didn't focus on romance at all, like Kami Garcia's, but the bulk of them did.
The Final Verdict:
The ideal audience for Shards & Ashes consists of those who loved the books of most of these authors. It's a nice quick read, and I think the stories will meet with approval from the fan base. If you're primary qualification is a world building, you might want to pass on this one.