[notimp]

Please qualify your statement. I hate it, when people try to push through a standpoint by their reputation alone.

You may win the public opinion, but you prevent others from making informed decisions.

Also - of course I disagree. If JBPatch is available on your firmware, you go with mobi.

.azw3 has some additional formating options (almost no one turned out to be using, because epub 3.0 didnt stick as a production format) but thats it from my POV.

Also .mobi files on Kindles are always displayed as "justified by default" - which eliminated the need to reformat most of them before you can start reading.

Nowadays you have to almost always tweak them manually, before you can go on to read them (hyphenation, justified text, ..).

If you want to know in what format you should store them for posteriority, the answer is always epub or - the most current open (/reverse engineered) format you can get your hands on (because of the odd possibility that someone took advantage of the new formating options within the format.).

The case that "newer is always better" from a usability and featureset standpoint on Amazons Kindles isnt as straight forward as you might think.