CCC has an asking price of $10, or whatever you feel it's worth to you. This is the true meaning of "shareware". This is different from the author stating their software is free. I've paid Mike Bombich $30 so far, and may pay him if I start using CCC 3.

I switched to SuperDuper about a year ago, after I got tired of CCC 2.3 hanging when it encountered bad blocks and/or bad files. SuperDuper is able to deal with these conditions better than CCC 2.3--it stops the copy, allowing you to read the log of the copy pass, to see the name of the file it hung at, allowing you to trash that file and start another copy pass--but maybe CCC 3 is better at dealing with these problems now, and not hang, though it will need to show the name of the files it can't copy. I also much prefer CCC's method of allowing the user to select which files not to copy, instead of the clumsy scripting method that SuperDuper requires, so that's another reason to try CCC 3.

But SuperDuper has worked great for me in the approximate year during which I've used it.