In comparison to a performed audio book, where a person reads the content, and reflects the emotion and pace of an author's work, ebook text-to-speech can sound stilted and mechanical. A blind or partially sighted person who is used to text to speech, however, may prefer it precisely because it is not performed, as it allows them to draw their own interpretation from the text.
Someone may prefer either performed audio books or text to speech depending on their individual preferences, the nature of the material they're reading, where they are - for example, at work or at home - and even the time of day.
However, the main advantages of eBooks with text-to-speech over performed audio books is the availability, ease of access and new titles becoming available much quicker.
A large and growing number of new and existing books are made available in eBook format, which may never be made available as audio books. eBooks that can be read by using text-to-speech have the potential to greatly increase the number of books available to those who rely on audio formats.