This is the first of a series of, I think 10. I didn't read this one first - I bought one at random as it was being promoted in the bookshop.
To be honest it's not normally a genre that I read, but there was something about the central character that I really enjoyed, and found myself totally gripped by him and the storyline. (I don't actually think this is the best one)
In the space of about a month I had managed to buy and read all of the series - and got his latest (in hardback) for Christmas.