Originally Posted by S-F
It seems like .pdf is generally a pretty good format because it's so versatile so I'd like to make all of my purchases as .pdf.
PDF is a very poor choice of format, because it's formatted for a specific page size - generally, a size much larger than that of an eBook reader. It's really the very last format that you should buy unless
you know that the book has been formatted for the screen size of the device that you'll be reading it on.