Spoke with DH about SRS. He recommends Dragon Naturally Speaking.
Here is the web address:
http://www.nuance.com/
Nuance is the company who owns the software. You will see many others they have purchased on the site.
He works on a very expensive medical SR software for hospitals and clinics. (And he thinks he isn't doing anyting important!)
Any questions, call the company or send me a pm or post. I'll ask Jim.
Best Wishes