This is a video of me dictating the text of this blog post.
I posted a longform article on how to use Dragon on my blog, which you can find here:
The short story is, modern dictation software works out-of-the-box. Forget about training, there is no training anymore.
With a fast CPU, lots of memory, a solid-state hard drive, a good microphone, and good pronunciation, you can effortlessly hit 100 words per minutes, or more if you happen to be the kind of person who talks quickly. I even know a number of people who have discovered themselves as authors thanks to the productivity-boost of dictation.
It does not take a crazy machine. I have a HP EliteBook, a i7 M620 2.67 GHz CPU, four gigs of RAM, and a Intel SSD. Perhaps the most important piece is the microphone. I used to have a Sennheiser headset microphone, which was great at cutting off the voices of people talking around me in the office. But then I switched to a self-standing USB microphone because I would rather not have something on my head all day. You can find it on Amazon.
The point is, the dictation is great.
In the video, I'm giving you a sense of how quickly I correct the recognition mistakes as I go along. I don't bother with "scratch that" or Dragon's other correction commands. You can see how I use the mouse liberally and I jump in with the keyboard when I know Dragon won't hear the word I'm about to type. The only words Dragon did not know about were i7, M620, and EliteBook (which I added to its dictionary beforehand). Everything else is built-in.
After dictating, I quickly scan the text correcting the mistakes, missing one ("it" instead of "hit").
All-in-all, it took 3 minutes to dictate about 200 words, including all the fiddling, which adds up to 66 WPM.