I bought a recorder that included that software, but I wouldn't recommend trying to transcribe interviews with Dragon. It is very time-intensive to train the software for one voice, and it is very sensitive to inflection, etc.
But the transcription software that comes with the Sony recorder is very good. You can stop/start the tape with F10/F11, which means you never have to pick your fingers up off the keyboard. I found transcribing with those to go as quickly as with a foot pedal -- and it's a lot easier to hear a digital recorder with clarity than a tape.
Next time I will probably pay someone else to transcribe, but I'm a grad student and it did make me very familiar with my data.