Split Second is a great idea hobbled by poor writing. To reiterate, because the following review sounds pretty harsh: The scifi story at the core of this thriller is cool as hell, terrifically well-thought out, and worth the price of admission. It's just that the writing is rough.
The science is excellent. The application of said science is damnably creative. The plot, a fair example of the thriller model, hums along at a good clip. But the writing...oof.
This is the sort of book where the dialogue all sounds the same. Every character uses that jaded, biting valley-girl sarcasm that has infected so much of our culture. For example: I'm SO not into this. Yeah, and I bet you're REALLY heartbroken. Oh, I TOTALLY believe you. This voice is fine from Buffy or some other Cali teen hotshot, but it's hard to imagine a special forces veteran talking this way.
This is a book where a submachine gun will ALWAYS be referred to as a COMPACT submachine gun. Terrorists will ALWAYS be referred to as 'barbarians.' Soldiers ALWAYS refer to each other as 'brothers in arms.'
In this book, the men are always MANLY men and the women, well, woman, is always given special credit from her male companions for pulling a normal amount of weight, or staying awake during a trying conversation, or not just going to pieces when the going gets (admittedly pretty hellishly) rough. Nobody congratulates the male civilian physicist for not losing it when the bullets start to fly, why do we need to stop several times so that the guys can tell the one female character she's doing a great job?
Split Second reminded me of peak Clive Cussler, except that when Cussler wrote the Dirk Pitt series, he at least had a charm and skill with his wordplay that distracted the reader from the vaguely worrisome conservatism that plagued every novel. There's a troubling vein of jingoism, sexism, and even classism running through Split Second, and the sub-par writing makes it hard to take at times.
Taken just as a thriller, Split Second is a decent ride, worth reading if you read fast and don't mind the occasional filler book. If you're willing to sit through the iffy writing, the science fiction, when it finally hits, is worth the price of admission. I can't stress this enough. My partner asked me why I kept reading a book I kept quoting in disbelief, and I told her, it's because there's a hell of a scifi story buried in here. I'm glad I read this book, overall. But I'm also glad it didn't take more than a day or so to get through it.