Take a look at Ace Studio, it is impressive for AI vocals, giving very minute control to the producer and it is trained ethicly. Once those fine tuned controls are in place, songwriters (in the near future) will laugh at those of us who worked 2yrs on a song, never to get it the way we envisioned it,...
Uh... yeah... I have ACE Studio. It doesn't pronounce the English language very well. Perhaps if I worked on a track for two years...
Don't get me wrong, I like it for demos but IMO, it's just not very good yet.