In a past life I was a print designer relying on Adobe software for everything, and it is tremendously liberating to be able to leave that world of vendor-lock-in behind (InDesign has a nasty habit of making each new version's files incompatible with previous ones). So compared to where I'm coming from, Prince (even as proprietary software) is a big step forward because it allows me to work in open formats.
[1]: http://www.getty.edu/publications/romanmosaics
[2][PDF, 8MB]: http://www.getty.edu/publications/romanmosaics/assets/downlo...
On a tangent, a very nice "win" with the (pdf)LaTeX approach is that it's fairly easy to collate other PDF documents into a larger one, with a custom table of contents, consistent running headers and footers, index of authors, etc., and intersperse them with other content from our database. (This was done by splitting the child documents into pages with pdftk, then inserting them as "PDF graphics" into the generated LaTeX document -- and as long as the original PDFs were searchable, they remained searchable in the final output.) In one of our paper-intensive processes (a proposal approval workflow), this approach cut down tremendously on manual labour that was being done to prepare proposal dossiers, and the resulting collation was much easier for the reviewers to work with (e.g., everyone could turn to page "K-34" in the dossier, and be certain they were looking at the same page of the same document).
This would be my issue with using it. This is partly why I stay with LaTeX for our book as I can convert it to other formats if I really need to. I find LaTeX gives me more control over presentation & type-setting than web-based stuff as well.
HTML and CSS?
Wikipedia lists some of what Prince does that others don't:
https://en.wikipedia.org/wiki/Comparison_of_layout_engines_(...