Fine Structure is a great piece of fiction, I started following it around the middle and stayed till the end... but I feel it could've been so much more. Sam started out with some awesome premises, but gradually wrote himself into a corner as the powers in play kept escalating. All the while, his writing skill was noticeably growing stronger and more confident, which is why the series stays readable up to the finale. IMO, the high point is the short story Failure Mode from the middle of the series. It reads like a description of what would happen to Eliezer's Harry Potter if one of his experiments went awry.