A few years ago (ahem... 1996-1997) when VR became the big business buzz I was tasked with implementing a pilot project for a large government organization. The goal was to get rid of stenographers and have extremely-highly-paid analysts do their own bottom-of-the-pay-scale transcription. Keep in mind it was government -- which meant that most of the people in these positions were 50+ and many had never learned how to type, and only started using computers because my prior big project forced them to.

Almost everyone abandoned the VR for various reasons... out of over 250 users, I think only 2 used the systems for more than a month or two. The error rate was within spec (around 95% after training) but in a page there would still be 15-20 errors that needed proof-reading and correction. Never mind the speed issues as well as background noise, answering the telephone etc.

The main point of this post is that a several people started to get problems with their voice -- sore throats and loss of voice -- after only a short while using VR. This was particularly alarming given that it was specifically targeted at one of these people due to RSI in her hands from typing.

The reason given was that in order for the computer to be accurate, people were forced to speak in a measured monotone, quite different from regular speech or using a dictaphone. This stressed people's vocal cords, some to the point where they suffered temporary voice loss for several days.

My advice: vary your speaking tone, don't dictate for more than say 30 minutes straight before taking a break, and drink lots of water. It would really suck not being able to type or speak.