I really like the Double Talk synthesizer, but, have no objections to Dec-Talk or Eloquence. I do know that some people are put off by the Double Talk synthesizer and might be more likely to buy the Book Port if it had a different synthesizer. I used Double Talk on my old Windows 95 computer and so had no trouble adjusting to it on the Book Port. I think each synthesizer has its quirks in pronunciation so it is probably a trade-off among the three mentioned, some doing better here and others there. I do not like the AT&T Natural Voices or Neospeech at all. To me they sound choppy and irritating to listen to. Joni