While I have some real problems with this book, I cannot agree with the one and two star reviews either. However, I have the benefit of knowing that this is not the end book of a series; if it had been, I would have been bitterly disappointed.
The book is better than the first two with some of the mysteries being, at least partially, solved and others remaining for the future. The solutions do not necessarily result in happy ever after endings but provide realistic resolutions to the problems involved. Sadly, we see less and less of the Collegium and more of the city of Haven.
There are, however, some matters that keep this from being on a par with earlier works by this author. 1) The matter of Bard Marchand is handled almost as an afterthought, as if the author was just tired of him and decided to make an end. There really is not sufficient explanation of his motivation in the actions he took (I am trying not to spoil this book for those who have not read it). 2) Mags' age? Mags was 11 or 12 when he was chosen. We have his own word for the fact that he had not yet reached puberty. He came to the collegium in the fall and the unusually cold winter started at the beginning of that book. The second book covered the balance of that winter and into spring. For the most part, we see Mags as an exceptionally mature young boy throughout. The third book starts with the exceptionally hot summer that follows so Mags should be about 12 or 13, maybe 14, at a stretch. But he is now acting and is being treated as if he were 17 or 18. The romance with Amilly is between young adults and not children and Amilly's father is treating Mags as an approved suitor. Ridiculous. 3) Mags' accent. When he came to the collegium, Max spoke with an uneducated accent and vocabulary. Perfectly natural, but it should be something the collegium is seeking to train him out of, not tacitly condoning. He should be required to use proper diction and vocabulary just to give him much needed practice in using the language properly. Heralds are required to interact with the nobility, to act as judges and to represent the crown. Failure to speak well will be a handicap when he becomes a young man but nobody seems to be doing anything about it.
In the end, I have given it four stars but I think there is a decline in quality overall.
For the rest, the book was fair and I am looking forward to the next - final? - volume.