If your monolithic backup suffers single a bit error, it's unrecoverable. If you zfs recv, though, you can recover all pristine files. And if you zfs recv to a redundant filesystem (mirror, RAID-Z), you can periodically zfs scrub and recover from those errors completely.
I've been running ZFS continually since about 2009, currently using its replication as a major part of the disaster recovery strategy for my employer, and in the intervening time having been through a number of disk failures, controller failures, etc.
Just chiming in here to say that I endorse every aspect of the answer that 7e has given you.
