Generally I think the use case is "duplicate the boot volume of my machine onto an attached usb drive" though I think these days not all Macs will boot from an

Generally I think the use case is "duplicate the boot volume of my machine onto an attached usb drive" though I think these days not all Macs will boot from an external drive? I have SuperDuper doing scheduled backups like this, along with Backblaze for offsite (but not so bootable) backups.