[rashkae]

Advantages to Kepub:

Much faster response to page turns. Kobos are better at this with normal epubs than they used to be, but the difference is still noticeable.. and is massive for books with graphic content.

Ability to Zoom (and pan) on Images.. Great for maps, or pictures with small print text.

Much more responsive to text selection, if you like to make annotations or text excerpts.

Better image display, with a fine grained dither that makes the e-ink 16 shakes of grey look just like a full greyscale image.

Reading Time estimate,, see the mostly accurate remaining time to read the current chapter, the entire book, as well as as a graphic chart that shows the relative length of chapters.

Footnote links will pop up as a window, instead of jumping around to a different page in the book. Also, the small footnote links are much easier to press without accidentally turning the page.

Font selection will fall back to a font that has any missing glyphs. That means, books with unusual or foreign language Unicode characters will display properly, even if the font is not embedded in the book (assuming they are supported on Kobo, I don't think Arabic languages are there yet.) This is about the only Kepub advantage left that I consider vital (I have a number of books affected by the Kobo's innability to handle this i n regular Epub)

As for converting, it's as simple as installing the KoboTouchExtended, KePub Metadata Reader and KePub Metadata Writer plugins. Calibre will automatically convert epubs to Kepubs on the fly when you use Calibre to send books to the device.

You can, optionally, install a Kepub Output Plugin in Calibre, that will allow you to convert to a Kepub that will be stored in your Library, but I don't see much point in doing so. It will only take up disk space, and will force the books through the entire Calibre conversion process, which might have detrimental or unexpected effects on the formatting if you aren't familiar with all the fiddly options.