From reading the Amazon customer reviews, this is a love-it or hate-it kind of book. This is only natural, as Simmons writes in such a huge variety of genres that people looking for "more of the same" will invariably be disappointed. I fall into the former camp for several reasons.
First of all, though many of the "accidents" in the story are well-known urban legends, the craft lies in how they are reconstructed. When confronted with the detritus of the infamous JATO car story, it would not be immediately obvioius to a bystander what happened or why. Dr. Darwin Minor has to figure the sequence of events out from a deep knowledge of physics and such things as tire marks. Far more interesting are the "real" accidents that are reconstructed; apparently, Simmons has a brother in the business and therefore has reconstructions of great accuracy.
Secondly, though some people have complained that Dar Minor appears to be good at everything (with the implication that such things are unrealistic), it is far more likely for one person with drive to be good at multiple things than to be good at just one. (I know people like that. I'm guessing that those people who complained do not.)
Thirdly, and perhaps most importantly, Simmons' writing is transparent. You are aware of the events, not of the wordplay constructing them. While that style of writing is against everything "literature writers" hold dear, it is especially useful in the suspense genre, where the action and not the writing becomes center stage.
This novel is about insurance fraud, of all things. It is to Simmons' credit that such a potentially boring concept is elevated to high drama, with car chases, aerial shootouts, sniper shootouts, and, of course, lots of accidents ridiculous and sublime. If you are interested in an enjoyable little thriller, this will do you good; if you're looking for another Hyperion, think of this book as being by a different writer entirely.