Worth every penny.
Needed to practice choir music, and the only iTunes recordings were in a different key. I imported each to MimiCopy and shifted the key for each to match my scores. MimiCopy maintains the whole list, and remembers which piece is in which key so I can practice them all in a row without hassle. Slow down and looping on a snippet are easy as well. Im recommending this app to all my musician friends.
NingleJingle about mimiCopy - Slow Down Player