In my experience, Speech to text has been a huge disapointment. I do give you that in the country where I live (Argentina) we speak a different... "dialect" of Spanish that what you've probably used to train your engine. Even then, it's entirely useless for my country, whereas Google has zero problems.
Very fair point. Our STT service, even though it is based on a technology with the very best results for public benchmarks, is not as robust to accents at the moment - for the exact reason you mention, we didn't train it on all the dialects. But that will come with usage in the field. Google has a head start on this but with the usage of our services growing quickly we will be able to catch up quickly.
Speech to text: https://developer.ibm.com/watson/blog/2016/04/28/recent-adva...
Emotion: https://developer.ibm.com/watson/blog/2016/02/29/another-ste...