Dragon Dictate, while an entirely local application, is extremely explicit in order to get it to work well. You really must dictate your punctuation in order for it to do a good job. While that is only a light impediment, it is an impediment.
In addition, it is only occasionally updated, and when it is, you are paying hundreds of dollars for a new version of the application.
In terms of development cycle, it's stable, but not particularly improving. Aqua Voice, on the other hand, is very much in a state of continual improvement, and the creators are extremely responsive.
While the buy-in for Aqua is on a monthly basis, the development that you get for it and the access that it provides is easily worth the $10 a month.