Lukyanenko does a good job of tackling the details of his concept - that humans are divided into 'naturals' and genetically designed 'speshes' who have had some aspects of their being enhanced and others suppressed. Pilots, for example, have innate mathematical skills and a firm belief in order, but are incapable of love. Lukyanenko pursues the concept with consistent logic, if with a little fuzziness around the edges, and with a massive over-simplification at one point.
Happily, Lukyanenko sets his book in a (far future) multicultural context, not the America-centric milieu that is the default for so many stories. Unhappily, he carries in a number of stereotypes that are outdated even in Russia - particularly concerning women and gays. (e.g., "every woman's ineradicable need to look as seductive as possible") Some elements don't ring true for anyone, and especially for a Russian. The book is presented by Goodreads as a sequel of sorts to Dances on Snow, but it reads as a standalone novel.
The book is partly about the risk of hubris - the fear that humans exploiting the near-divine power of genetic pre-determination sow the seeds of their own destruction. It's also a novel about love. Alex, whose ability to love is genetically inhibited, is pushed by circumstances to explore his limitations. As one character tells him, "love is the feeling that makes us equal to God".
Some aspects of the story are imperfectly developed. Alex has a tattoo on his shoulder that shows his emotional state. The need for and purpose of the tattoo are initially unclear, and never really developed. It's a promising gimmick, but one that feels like the remnant of an early draft. There's a (non-graphic) scene of sexual violence that's completely gratuitous and non-credible, and feels inserted solely to get the plot around a corner. Kim is inconsistent in her knowledge of her self and skills. The book evolves partly into an homage to Agatha Christie and Arthur Conan Doyle, but the detective element is not the book's strong point.
On a purely conceptual level, this is a well developed and executed book. Lukyanenko sets out to consider the benefits and drawbacks of genetic manipulation, and does so logically and thoughtfully. The writing is generally good (the translation is good, but not great). Unfortunately, the presentation of concepts is substantially undercut by tired and offensive biases. Had the book been written in 1950, or even Russia in 1970, I'd have made allowances. But it wasn't; it was written in 1999, well past the time when these flaws could be overlooked. I'm (very slowly) reading Lukyanenko's Watch series in Russian, and I have to say that this has made me a fair bit less enthusiastic to press on.
If you're intrigued by the potential consequences of genetic engineering, and can stomach the unfortunate attitudes, this is an interesting book. If sexism and prejudice get in your way, I can't recommend this.