This was a really delightful book. I was initially skeptical, but it ended up as a very interesting and well-written take on the whole magical school portal fantasy genre. The criticism/subversion of the genre certainly started out rather heavy-handed, but it developed in nuance and elegance as the characters matured. The main characters were really delightful; I enjoyed the prioritization of platonic relationships over romantic ones, and I think the combination of the two was well-balanced. 
The character development was remarkable and very well-paced. The protagonist's pov was irritating for the first section of the book, but that became much better-balanced as the book progressed.
I don't think I would get it again, because I think it would be frustrating to read substantial parts of it knowing where it is going, but it was a very enjoyable read the first time through.