I've read a lot of fanfics (roughly 20 million words), and this story is definitely in the top 10. I really like the pacing of the story. It feels like the characters are alive, their interactions are well written. I don't understand those who give it less than 4, considering how full of slag this site is with the same or higher ratings.
Many of you will say I read a lot of crap, and I'll say "yes", but that's why I can tell the difference between crap and good work.