Very nice! Ever heard a vocaloid sing in Spanish or Russian? Surprisingly good stuff, despite not being designed around it.
An example.(youtube.com)
Miku always sounds cute to me, but I'm not sure on the pronunciation. I listened to some Miku singing English songs before the English voice bank was released, it was basically Engrish.
Miku cover of Heaven is a Place on Earth. https://youtu.be/HATpOha7DFg
(post is archived)