I read the book, years ago, and found it to be excellent ...

I read THE NINTH CONFIGURATION last year, and found it entertaining, but also very silly and heavy-handed (it was often laughably overwritten). I've not seen the film yet, though I want to.

I've seen the film a few times and really liked it a lot. One of those slow-burning cult classics that finds its audience years after the cinema release (like Withnail & I for example). I know Mark Kermode, the British film critic who wrote the BFI book on The Exorcist, also wrote some articles and an introduction for the published script in praise of the film a while back.