before i buy a dedicated raid 5 box theres something id like to clear up. What happens if the box itself goes down. In this case can the drives simply be installed in any other raid 5 controller and be brought back online? Or are the drives tied to the controller that set them up?
You generally should use the same card or housing, as they may or may not be compatible with others, and even with identical equipment there are issues and there is no sure thing.
What box are you considering? And how many drives, drive quality, and drive size?
Always remember that a raid array is NOT a backup, but a fault tolerant storage. You still need to do real backup to protect important data.