Yes, I'm creating more versions of the same book, for two reasons:
1) I'd like to create a template of best conversion settings, in order to have not crap switching from epub or kepub and characters size. Probably the best thing will be to install patched firmware. But for now I'm very happy for the ereader, it works like a charm
2) I wanna learn to use Calibre, so for me it's funny make tests and experiments