OK, I've decided that I want to move from having the two drives in my Mini treated as two separate drives to having them formatted as a single drive with RAID. The question is, what's the current best practice for doing this migration? I've got a large external drive that I can back up to. Can I do the whole thing with a Time Machine backup or do I need something like Superduper or Carbon Copy Cloner to make sure I get the whole disk copied over?