The Product Description gives reasons how the device-to-device copying of this app can be useful (e.g. filesystems for other operating systems). However, if you don't need that functionality then other "cloner" apps will be a better value. For example, SuperDuper! is free for doing full volume clones and its Smart Update feature (if you pay the shareware free) is much faster and more reliable than Carbon Copy Cloner's psync. Btw, Carbon Copy Cloner is shareware, not free (a common misperception).