This is generally a well written book with good characterisation and much thought in differentiating the 'aliens' in the story.
The main character (for me) Commander Cook is a mixture of genius, arrogance, has impossibly high self standards, and is socially aware of those in his command (ie he is human towards them and interacts with them). There is also the undertone of a romantic involvement with one of his officers.
The book is really a prelude or introduction to setting the stage for the rest of the story (I am part way through book 2 and waited to write this review) and as such does not so much end as peter out in a fizzle (although leaving you wanting to read more). Much of the book revolves around Cook's ability to get a new space ship up and running due to the Contractors who built the ship having cut corners in virtually every area of the ship. (There is also background on Cook from a young man to how he got his commands).
I have not found this book to be a page turner as I found I was more interested in Cook and his exploits rather than the background to the aliens (more comes in the second book - so it was interesting enough for me to carry on). If you enjoy strategy and politics then I would guess that you will find this book interesting; as would someone who enjoys some engineering descriptions added in to the mix.
Update 13 April 2011 Updated the overall star rating to Five. While I do not agree with the story breaks for the three books, the overall story is fantastic and for me turned out to be a page turner (having stuck with the story). All of it is well thought out with political nuances and manoeuvring, big space battles, heroes, tactlessness etc. Book 2: The Star Dancers (The Guardians of Peace) Book 3: Clouds of Darkness (The Guardians of Peace).