[DiapDealer]

I've never had a bit of trouble with fonts not displaying properly (italic or otherwise) with Bookari/Mantano. I can also force left-align on the vast majority of my books that typically default to justified. I assume the few epubs that I can't use Bookari to force the different text-alignment are doing something funky in the epub to prevent it. *shrug*

EDIT: Never mind, I see what you mean about the fonts. I've just never used anything other than the default font (or a personalized font in which I supplied all 4/5 font-files necessary). But I still have no problem overriding default text-alignment (except for the few epubs that prevent it by having "unwise" internal formatting).