I've messed around with Api.ai (https://docs.api.ai/docs/tts https://docs.api.ai/docs/tts) and it is quite impressive. Full-featured, amazing pricing (free), an

I've messed around with Api.ai (https://docs.api.ai/docs/tts https://docs.api.ai/docs/tts) and it is quite impressive. Full-featured, amazing pricing (free), and goes way beyond just TTS.