[J. hunter Allred]

To add to that, if you don’t back up to other media, I’d consider 4 drives, 3 in raid 5, and last as a hot spare.

Personally, I’d get one 3TB drive, raid5 together your 3 1TB drives, and use the 3TB as a timemachine volume. Then you’re somewhat protect from file deletions, corruptions, alterations, etc, in addition to plain old disk failure