CCC is a subset of klone. Klone could be though of as a combination of CCC (ditto) and RsyncX's features.
Rsync allows klone to update a drive rather than just copy the files. In a few minutes, it can turn a week-old CCC/klone snapshot drive into an up-to-the-minute updated copy.
It can also exclusively target the /Users folder, when accessing a drive causes the drive to shut down, or when time is critical. I've dealt with a few dozen drives that only allowed me ~4-5 minutes of access time before overheating. (or LESS!) Back into the freezer for 10 min. back out, to run klone again to resume saving just the /Users folder. A few of them required all afternoon for complete recovery. Try that with CCC
Surprisingly, klone makes CCC look like a one-trick-pony.
(will CCC even do non-HFS drives? klone will)
I also don't think you can CCC off a diskwarrior preview? Most disk imagers require unmounting the volume during copy, and that causes DW to disconnect the preview. THAT was my bread-and-butter use for Klone. Also, the ONE thing that will reliably kill ditto is duplicating from a drive with an open and dirty journal. Unless they've found a way around it, CCC will hang on such a drive. Dozens of times I ran into a drive that required a DW preview to get it on the desktop, and it had a dirty journal. Can't delete it because the preview is read-only. Thus ditto (for the entire drive) is not an option. Either ditto /Users only to avoid encounting the journal, or rsync then entire drive, because klone tells rsync to skip that killer file. (ditto cannot be told to skip a file) CCC offers neither option. (klone can also copy everything EXCEPT /Users from a failing drive, for cases where you need proprietary software fully recovered because reinstallation isn't a good option)
Trust me, if CCC did what I needed it to do, I wouldn't have spent all that time developing klone.
On a sidenote, I have another smaller script that specifically uses rsync for syncing volumes (boot or otherwise) either locally
or over the LAN or even over the internet. Rsync is an excellent tool to have in your kit for automatic offsite backup.
