This is a good alien contact series. I liked how the Rakhat society has been explained. The assumptions and their effects on various characters, humans and aliens, are gradually revealed.
The only part I did not really enjoy was how solidly christianity (or at least a branch of it) is a part of this. Coming from a non christian background, a lot of the nuanaces went totally over my head, and even the ones I vaguely caught did not really create a great impact. So I guess what I am saying is that it may be a bit difficult to really appreciate all aspects of this series if you have
1. Not much interest in religion.
2. Not much exposure to christianity and its scriptures.
Otherwise a thought provoking series.