I don't see people mention Smashwords around here very often. I remember there used to be some controversy with the Smashwords "meat grinder" that turns Word documents into EPUB files and often mangles the formatting.
Would I be correct in assuming that if Smashwords only offers EPUB format for a book, that the author probably uploaded a finished EPUB file, and you're getting the same file that you'd get on other stores, whereas if Smashwords offers TXT/PDF/EPUB/MOBI that the author probably used the meat grinder method, and the formatting is more likely to be spotty compared to getting the book at another store?
I'd be interested in supporting an independent store, but not if I get mangled books in the process.
