Just read their licensing agreement and it talks mainly about development.
In summary it says you can purchase the SDK to develop, but this "...in no
way" permits the redistribution of the voice engine. It doesn't say
anything about redistributing the files created with their engine. My
instinct isn't good though as what I just read seems to suggest that they
use hardware keys to protect their sdk, (unless you buy the one for mobiles;
in which case it's a software key). That level of paranoia doesn't auger
well!

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