The story was relatively interesting, if a bit dry. The biggest problem I had with it was the lack of continuity with the rest of the series.
This book chronologically takes place a short time after Black Trillium. That would be fine if May and Norton had discussed it, but the lines of communication apparently failed.
If May knew how Norton was to conclude her story, she must have ignored it, because the character traits displayed by Kadiyah in Golden Trillium were not displayed by her in Blood Trillium.
Overall, I prefer the Kadiyah of Golden Trillium, to her through the eyes of May in Blood Trillium. I wish that something of that had been carried on.
The World of Three Moons did not seem the same world as that in the earlier works, or the later works. The appearance of the Sidonna didn't match the reference to them in the later works. It also did not have the strength of The Trillium due to the limited role of Haramis (maybe a paragraph), and the non-appearance of Anigel.
I do not think this is the best of Norton's work. If you are interested in the ongoing storyline of the World of Three Moons, you can safely ignore this book and miss none of that storyline. If you are an ANdre Norton fan, try to find it second hand.