Justine Larbalestier, a very good novelist with very bad RSI, has written a great post called "Why I Cannot Write a Novel With Voice Recognition Software." In it, she explains why machine-based speech-to-text software isn't sufficient for fiction. I think that if I absolutely lost the use of my hands and had no other choice, I'd probably dive into speech-to-text and gut it out, but nothing short of absolute necessity would get me to write fiction with machine-based speech-recognition.
Most of my first drafts are written in a gush of words as the characters and story come flowing out of me. Having to start and stop as I correct the VRS errors, and try to get it to write what I want it to write, interrupts my flow, throw me out of the story I'm trying to write, and makes me forget the gorgeously crafted sentence that was in my head ten seconds ago.
Now, yes, when I'm typing that gorgeously crafted sentence in my head it frequently turns out to not be so gorgeously crafted but, hey, that's what rewriting is for. And when I'm typing the sentence it always has a resemblance to its platonic ideal. With VRS if I don't check after every clause appears I wind up with sentences like this:
Warm artichoke had an is at orange night light raining when come lit.
When Angel was able to emerge into the orange night Liam's reign was complete.
Which is a terrible sentence but I can see what I was going for and I'll be able to fix it. But that first sentence? Leave it for a few minutes and I'll have no clue what I was trying to say.
However, checking what the VRS has produced after Every Single Clause slows me down and ruins the flow.