Thanks for all the comments!! Could you educate me a little bit more? I'm still fuzzy on the difedence between
copying and cloning. I've been using SuperDuper for years, every night. It just adds the new data since my last backup. Is it copying or cloning? What is a sector level copy? What is the difference between replicating the file system and not just the files? Thanks again!!
For practical purposes in relation to doing your backups, the answer is "it doesn't matter" :-)
But for you general interest, it basically boils down to this:
1. Cloning (real cloning) means making an identical replica. So if Drive A is cloned to Drive B, so far as any computer looking at it would think, they are the same drive in every respect. The formatting of the file system, the attributes of files, any errors etc, are all transferred over as it's not looking at whole files, but rather the sectors on the hard drive and copying them over. This is where programs like Ghost live in the scheme of things and it's used when you want to exactly replicate a drive (for example, rolling out a particular build to multiple computers, to avoid having to go through the installation process on each one).
2. Copying is copying. As Schewe noted, there are different levels. Some just copy a file and the new copy has a new timestamp and different attributes etc. Some do an identical copy, which means the copied file looks exactly like the original one, but could be anywhere - not necessarily cloned onto an identical device. This is what good backup software does (as well as making copies of all the hidden files and so on). You can also do it manually if you know the settings.
What your SuperDuper is doing is normal, incremental back up. This means it has an original version (the first time it backs up) and then it just has new/changed/deleted files in the incremental backups, meaning it's pretty quick and easy. From time to time, most people do a "full" backup, to give a new starting point and so that the incremental changes don't go on forever (incremental backups do have some minor risks if left for a long time but I haven't really heard of serious problems in a long time).
Essentially, backing up using SuperDuper or CCC or any of the other software mentioned from one array to another should work very well. Don't worry about "cloning". Do consider having a non-RAID backup of your stuff, though, so you're not reliant upon specific hardware or software to recover your data.
Hope that's been of some assistance!