I'm on the fence on this one.
When it started with a clone army, I groaned. I've seen a bunch of stories with big groups of clones as the protagonist and they rarely appeal to me. I'm not sure why, it just seems like the characters, despite differentiating characteristics, are just too similar.
It bothered me that they decided to wage warfare on this thing because of nightmares. And then continued on that path even when there's hints of sentience: "Well, we decided to attack it, so we're attacking it" is about as ironclad as the parental justification "Because I said so". That wasn't really a flaw in the story though, just something that bothered me with its plausibility.
But I do like a couple things in particular:
1. Meeting with aliens where method of communication is not obvious, and may even be impossible.
2. The exchange between #5 and Dad "You thought you mattered." Ouch!