Sadly I got rid of the book scanner in my last house move, sorry. It was way too bulky to leave at the space, and it was quite temperamental & required a lot of post-processing.
We used it to scan a few books, and the only benefit to using it over other means was that the framing was super repeatable, and the glass platens held everything flat.
If you have access to an A3 office photocopier it'll likely give you better performance and be quicker. The only downsides are you have to pay attention to the alignment, and that pressing the book flat enough isn't polite to the book from an archival point of view.
Cheers,
Gavin