Coincidentally, I've also used pagedjs for a project recently (125K novel) and encountered some bugs/minor issues. Overall though, I would say I had an immensely positive experience (because even when stuff broke, it was still just HTML, CSS, and JS--so I, like any other web developer, could fix it).
That said, it's a shame that the relevant W3C specs (see https://pagedjs.org/about/) still aren't fully supported by browsers (but perhaps such is the fate of niche features), but with that being the case, I'm infinitely thankful that pagedjs exists as a polyfill.
That said, it's a shame that the relevant W3C specs (see https://pagedjs.org/about/) still aren't fully supported by browsers (but perhaps such is the fate of niche features), but with that being the case, I'm infinitely thankful that pagedjs exists as a polyfill.