I've used ASD pretty extensively. That is, until I discovered Audacity. Audacity does everything I could need more effectively than ASD, and for free. ASD's speed at slowing the tempo is definitely faster, but Audacity has higher sound quality, and once the song is convereted into a slower tempo, it plays much more reliably. Had I known about Audacity, I never would have paid for ASD. Audacity definitely has a much higher learning curve, and definitely does not provide the equalizer capability that ASD does, but it still is far behind as far as sound quality and reliability when compared to Audacity. Anyone thinking of paying for this software should definitley try both the demo of this software and the full free version of Audacity before forking over their cash; I wish that I had done the same.