Iirc SCP supports resuming transfers. Granted torrent architecture is very robust, but I’ve never had a problem with the way scp resumes work.

To resume, someone would have to notice the failure and start it again. If this happens every few minutes, it's effectively impossible. Even once an hour means their overnight transfer is impossible with scp.

Always use rsync. It's almost drop in compatible with scp, you could probably alias it for most uses, but it's more robust against failures and has more features.

That’s actually a good point, and it’d be real easy to spread to a third person were it necessary