I actually rather enjoyed this one. I had no idea what to expect when I picked it up - just started reading and while it was a bit slow to get started - I mean, lets face it, a history lesson about the prison and the area surrounding it is not exactly the greatest hook in the whole wide world - it soon picked up the pace and I had trouble putting it down.
The twist at the ending was not only unexpected, but rather gratifying. It was obvious on retrospect, but on the first read it was not a direction I was guessing at.
I found the main character both obnoxious and likable. Perhaps because you could see the obnoxious behavior was somewhat deliberate and not necessarily his real self. By the end I almost liked him.
I did find it a bit confusing - the main character's age is never specified, but there is an odd balance with his age. In some places he seems no more than a boy (12-14ish), what with them holding him down to whip him, being carried up to bed, the way he needs to sort himself out with the apprentice, the general way the magus talks to him, as if to a child - and in other places it seems as if he should be older (18-19-20ish), his ability to fight, talk of his marrying, etc. But nowhere is it actually specified how old he is. It is a trifle confusing.
All in all, it was a very interesting read and I am looking forward to the rest of the series.