I liked it. My forte's more with Alien fiction, I've not touched on Predators too much, but I liked the action. As I read it, I could flesh it in my mind, and imagine it would work really well as something from a novel, too: You should maybe give that a try?
Something that I didn't follow, though: if someone was hit with an implosion device, I wouldn't have thought that anything would fly OUT - more sucked in on itself? Instead of a shower of gibs and gore, I would imagine they'd invert into a shapeless quivering pile of raw meat... Maybe it's the sadist in me, but I like to imagine that they'd stay alive for as much of this process as possible... nothing like the gurgling death cry of someone choking on their own trachea to make you sit up and hit the reverse button on the DVD player to watch it again...
But I liked it.