If you like Catherine Coulter you will like "Tailspin". It has all of the notable elements present in all of her work and she does not fail to deliver. That being said, this is the third or fourth novel of hers that I have read and I realize I am not a big fan. The convention of the desperately-in-love FBI partners with the adorable little boy just does not capture me the way I wish it would. Because of the certainty of this relationship she is forced to introduce alternate leading characters to be able to build romantic friction and intrigue. I do not find anything interesting in a solid, steady relationship. That sounds jaded but it's true. The cardinal rule of story telling is to take your main character, discover the worst possible thing that could ever happen to him and then make that happen. It creates drama and intrigue and action. When we know that the main characters are loyal and devoted we have to look elsewhere for drama.
Personally, I would love to see one of these two people, the woman especially, become attracted to someone else in a very real way that threatens the idyllic bond between them. But that's just me. As I said, as far as Catherine Coulter novels go, this is as well done as the others and if you are a fan you will not be disappointed.