Okay, finally finished and have some thoughts. SPOILERS ABOUND
Pros: Much better than Seize the Fire. StF I had trouble even reading. With FG, I kept reading fine, and didn't get bogged down. I thought FG had an interesting story at least, wanted to see what would happen next.
Cons: Sigh. There was so much potential never followed up. If you are going to create a new alien race, make us care about them. That was almost nonexistent, especially at the end. You start the book with these two groups, and really almost give us nothing in the final moments. Anything about what happens afterwards? Trashers realize their mistakes, or not? Fighting continues? Flesh this stuff out, make me care! Follow up on your beginnings rather than, in the end, making it seem like nonessential fluff.
The whole Andorian situation and trickery was not... well written. I understand he was trying to layer the plot with some mystery. "Wait, she's dead? Who's back on Titan? What's going on?!" Yet, the mystery was not written well. It was confusing, to the extent that I actually thought I was missing something and kept flipping back to see what chapter I must have skipped. It wasn't until later I realized you were meant to be kept in the dark, but it just came off awkward and clumsy.
Why bring back Second Gen only to immediately return to the previous book's status quo? That was weird. I understand the end of the book leaves it open for Martin to revisit Torvig's plan for Second Gen as well as the Andorians on the Therin, but still, it felt weird. And wasn't a plan of the whole transporter duplication plan. As others have pointed out, I know the Andorians are pissed at the Federation and whatnot, but really, sinking to new lows with the Tholians this quickly? Tholians, yes, this has been established, but this seems a like a low, sickening plotline and I don't really see it. Maybe if Martin had given us more insight into the Therin's captain, and his motivations, and whatnot but he came across as a two dimensional character.