[dnanian]

No, you're quite right. Network backups are not nearly as robust as direct to drive backups. That's why I recommend them as secondary backups, not primary ones.

You also cannot properly preserve all the data you need to on an AFP/SMB device. So you'll end up with a "lossy" backup. You don't want that either.

As I said, iSCSI volumes act as truly native volumes. You can back up directly to them, over a network, with no loss. I do this all the time. But network connections are inherently less reliable than "physical" connection to a drive, regardless of their convenience.