I read a review somewhere that told me to check this out of the library instead of buying it, even if I super hearted Neil Gaiman. It was excellent advice, and I humbly thank the Minneapolis Public Library for the use of their book.
Anyway, the prologue told me what I should have known: this story was originally thought up as an idea for a series, then languished, then the authors got together to write it out in novel form to shop around as a series, then it languished some more, and ten years later, they dusted it off and published it. Whoo-hoo! Reheated leftovers!
It's not totally bloody awful or anything, but it's obviously Sliders meets Jet Li's "The One" meets Willow meets the Borg. With maybe a kind of Doctor Who-ish sensibility without all the British micro-budget silliness. Oh, and let's set the story initially in Illinois, but not have the dialogue edited for unwitting Britishisms. Cuz that's kicking ass and chewing bubblegum, only without the bubblegum this time.
So, if you want to be completist about your Neil Gaiman, go for it. Otherwise, give it a pass. Or wait, also, you could be a teenage boy and have delusions of your inherent specialness that will make you unique to save the multiverse some day. Then have at!