Upgrading from 8.1 to 10.3

Yes, 8.1, guilty as charged. :)

That said, this is old, slow, remote hardware with a ZFS on root setup.

In my day job, I don't mess with freebsd-update yet as it's relatively quick for me to simply stick with my trusty-since-4.x method of building world on one fast host and then running an installworld over NFS for my other installs.

This host is slow, and I'd like to get it off the "buildworld" train and start using freebsd-update. Does it seem wise to attempt this on 8.1? Does freebsd-update support jumping more than one version (8.x to 10.x)?

Any good general pointers for a freebsd-update n00b?
That would be a big jump for a binary upgrade. The general recommendation is to go through the middle versions rather than one big jump. So 8.1 to 9.x to 10.x.

Beyond that, I don't know. I've never used freebsd-update(8), and pkgbase should make it go away in FreeBSD 11.1.