Everything here is my opinion. I do not speak for your employer.
In which Attic wins, even though it corrupts his data. But it does it fast! Bup was the only one out of the three that both finished and didn't corrupt anything. But it took more than twice as long. Lame.
(Thanks to Will Angley for the link.)
Try Tailscale: mesh networking, centralized administration, WireGuard.