SuperDuper vs CCC Question

The free version of SuperDuper is equivalent to CCC. If you pay the $27 for the licensed version of SuperDuper, you can perform incremental backups (called "smart backups" by SuperDuper) that will back up only changed files to give you an updated, bootable clone. I use SuperDuper for my backups.

Hope this helps...

CCC is simply a front-end to UNIX' rsync. It compares the file modification time stamps of the old and new files, and, if different, then compares chunks of the files (changing on the chunks that have changed). It should not arbitrarily update files -- if a file IS being updated, it implies that there must have been a change, even if you don't know what process changed it.

I don't know if SuperDuper uses rsync to do it's dirty work or if it's a completely different approach. I would guess that it probably also uses rsync.

Time Machine monitors a system log that records when changes are made to the contents of a directory. When it comes across entries that are prior to the most recent update Time Machine has made, it goes to that directory (many documents in OS X are actually directories of multiple files) and checks for files that have changed (skipping subdirectories because they would also appear in the directory content change log). Any files that are newer than the most recent copy are copied over in their entirety (not the changes, the whole file) to the Time Machine volume.

Time Machine performs the backups constantly in the background based on the log of directories whose contents have changed, whereas CCC and SuperDuper do their backups on a regular schedule. Time Machine knows, from the log, which specific directories have experienced a change, whereas CCC and SuperDuper check everything on their predefined files and folders to check.

SuperDuper is not going to give you a different result than CCC with regard to speed, etc. What it will do is provide you with a more flexible UI for specifying and scheduling backup jobs.