A new WordPress version is in development. Peaple who uses the PDF24 WordPress plugin and who miss a feature then it's the best time to make a feature request.
The WordPress plugin site is located here:
http://wordpress.org/extend/plugins/pdf24-post-to-pdf/
If you do not know the PDF24 WordPress plugin, the above page gives you detailed information. Summarized the plugin converts articles of your blog to PDF. After created the user can download the PDF file.