I own a copy, and seeing as how it's one of the few Sliders collectibles out there, I don't regret buying it. But its infamous reputation is accurate.
There are a number of inappropriate crass comments in the book (for instance, in the "Time Again and World" review), and a number of bewilderingly wrong episode descriptions that suggest that the author, Brad Linaweaver, hadn't actually seen the episodes. For instance:
--He praises the "Weaker Sex" episode because he claims that "after an attempt is made on Arturo's life, Wade has a change of heart and questions the wisdom of the Sliders' involving themselves in this world's politics." In fact, she does nothing of the sort. She remains rather smug and defiant of Arturo all the way until the end of the episode. (Actually, I would like the episode a little better if the above scene happened, but it doesn't.)
--He claims that, at the end of "The Young and the Relentless," there's an epilogue that shows one of the denizens of that world having been captured by the Kromaggs, as a lead-in to "The Invasion." That simply doesn't happen.
--According to him, "Murder Most Foul" ends with Arturo not cured! "He slides, still thinking he's Reginald Doyle." Um...what??
--The description of the series on the back cover reads: "Following the success of The X-Files, Sliders has become a cult classic in its own right, attracting the many fans who follow the world of the strange and supernatural." WHAT??? NO!!! Sliders is not a show about ghosts and goblins! Why is this publisher even doing a book about the show if they apparently have no idea what it's about?? (On this last point, Linaweaver may not have written the back cover description.)
As for the rest of it: To be fair, perhaps Linaweaver had to work in a hurried fashion, and instead of video copies of the episodes, he had to work from early scripts. But it would be still weird that no one gave him the final scripts, at least. Admittedly, this is all speculation. But certainly, this was long before the beautiful Mill Creek set.
Anyway, due to the errors and incompleteness of the work, I don't think it's worth $20, but it's nice to have on your shelf somewhere as a Sliders collectible if you can get a decent price.