Booktype is for collaborative book production, so a solo writing demo says little about whether another platform will fit a publishing team. Try one short chapter with an author, editor, and production reviewer. Observe how each person receives changes, resolves conflicting edits, and approves a final version.
Export the same sample to every format you actually distribute. Inspect headings, images, footnotes, and tables rather than judging the cover alone. If your workflow requires translators or multiple editions, test how those branches are maintained after publication. A move is worthwhile only if the team can reproduce both the editing process and the published files without rebuilding the book by hand.
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