Night and day. I hardly hear of anyone using LVM snapshots except in special cases, but ZFS snapshots for many people are like brushing one's teeth: a habit that is done multiple times a day.

Using them for system updates/upgrades is built right into FreeBSD (copying a feature from Solaris):

* https://www.freebsd.org/cgi/man.cgi?beadm

If the changes fail just rollback the system to the previous state/snapshot (including kernel changes) via the boot loader.

Services like rsync.net allow one to have offsite backups with easy, and the destination can be encrypted such that the remote end can't see your data. All through an SSH pipe.