The title of this review sums up my feelings on Zindell's Ea Cycle as a whole: flawed but beautiful. I agree with previous reviewer "The Ringess" in that Zindell's usage of a first-person narrative severely, even fatally, limits this work. Oftentimes the protagonist, Valashu Elahad, "tells" us what happened off stage, and thus Zindell is cornered into committing that most egregious error of fiction writing: "telling" more of the story than he "shows."
That aside, The Diamond Warriors completes Zindell's Ea Cycle, one of the very few fantasy series to deal explicitly and implicitly with themes of a spiritual nature in any depth or profundity. The cosmic-spiritual context of the Ea Cycle is exquisitely wrought and literally dwarfs most fantasy milieus, avoiding the usual extremes of the Scylla and Charybdis of modern fantasy: conventional cliche or unconventional novelty. The former ends up being a juiceless formula, the "same old, same old" of tired post-Tolkien elves-and-dragons fantasy; the latter tries so hard to be "avante garde" that it ends up being a superficial cliche in its own right, an instance of its own complaint.
While Zindell as an author may be unparalleled in the field in terms of depth of consciousness, the Ea Cycle as a story falls short of the upper echelon of modern epic fantasy classics such as Steven Erikson's Malazan Book of the Fallen or George R.R. Martin's A Song of Fire and Ice. Put the Ea Cycle in the next tier down with R. Scott Bakker and Robert Jordan.