content: Yeah, I hear you on that. I had looked at these several years back as well and they were atrocious.  I think you may be better off using something like AWS polly in the current day and age if you were seriously trying to do something of this nature TBH.  I've never used it, but a buddy that does IVR systems said that the service works pretty well. I see Azure has a speech to text as well now, for what this worth.