Anyone have, or have experience with, Dragon - Naturally Speaking, software?

Saw a few TV commercials about it, decided to try and learn a bit more about it. Asked at Staples today, seems there are THREE versions:
1. Basic Dragon
2. Premium Dragon, $100 more, you can speak spreadsheets
3. Ultra Dragon , $100 more than Premium, wireless.

I know I don't need the wireless version.

So, anyone have any info?