Forget Via Voice (IMHO) as while it is a fairly good price it has its problems, is resource hungry and I had constant problems with the backup files.
Some time ago i switched to Dragon naturally Speaking V.6 PREFERRED and have not looked back - so much so that I have just upgraded to V.7. which will now ever insert punctuation automatically.
Not cheap at £150 but worth it. Make sure you go for the preferred version rather than standard or essentials - there is a vast difference.
I still have V.6 which I have emailed you about.