The first book in the series, Spin is a really great science-fiction story and the Hugo award it won is well-deserved. Since it is a story that can be easily spoiled, I’ll try to sell it without giving away too much: it is a story of a crisis that hits the Earth. The first book is mostly about unraveling the nature of this crisis and what caused it. What makes the book great, of course is that this crisis, called “the Spin”, is an interesting idea.
The latter two books– Axis and Vortex are okay-ish. They’re not boring books per se, it’s just that as follow-ups to Spin, I think they do pretty poorly. I think the problem is that while Spin introduces a fairly novel concept, instead of expanding upon that, Axis and Vortex spend a lot of time on mundane and overused-in-scifi stuff like how the bad guys are going to mis-utilize some technology.
So yeah, in summary, at least the first book is worth the read. If you are the kind of person who can live with reading only the first book of a three-part series, then I’d skip the latter two.