he never upgrades anything. He's not computer savvy; that computer hasn't been updated in years. IME, the longer the time between upgrades, the more chance of breakage. This way, he got an up-to-date install.
the drive sizes are different, and I wasn't about to try to walk him through resizing a partition and filesystem over the phone
there was very little he needed to keep from the old computer. He didn't install software; it's a web browser terminal
it wouldn't have helped the biggest problem we had, which was getting into a BIOS I didn't know and couldn't see, and changing it to boot from the USB stick. We'd have had to do that to do an image replication either way