The only thing that Calibre can't and that the Sony software can, is to pre-paginate a book. With Calibre, it means that when you open a book
for the first time, it will take the Reader a minute or two to process the book. If you change display size, it will need to process it again (but only one time for each size). For me it's not much of an issue, and as I prefer LRF format and convert everything to LRF, I just set the base font size to my preferred size.
Unless you want/need to carry around many hundreds of books, I'd suggest using the internal memory - or use cards for different smaller collections of books. More than a 100-200 books is a bit to wade through, even if it's sorted in different ways. At least that is what I have found works well for me
