Reading this book is an interesting experience; one gets so used to seeing the narrative through a Prussian focus that one automatically thinks of Fred as the hero and the central figure. Duffy rapidly sets that right, and within a few pages one is cheering for the Austrians - who turn out to have been capable of intelligent and decisive action on many occasions. It's not easy reading - I see myself going back when I have more time and paying proper attention to the maps - but that's a good sign with history; one isn't reading a facile Hollywood (or Carlylian) story. People who read the later years bits are also sure of a hearty laugh at the most original order for a cavalry charge ever issued (it makes Raglan's order to the Light Brigade at Balaclava look professional!).
There are a few signs of careless editing in places; grating missing apostrophes and the like, which are not Duffy's usual style. Otherwise, highly recommended.
If you need a day to day history of the Austrian army in the SYW than this is your book. Some maps and other niceties but almost all content is directed towards detailing DtD activities of the army. Also, there are better works, IMHO, on individual battles.