Kiwi,
I'm not sure which South Island you're talking about but all of our Service Lines Overhead or Underground are protected with 63A HRC English Electric fuselinks here in Ashburton.
The days of re-wireable gear has long gone and although we are still taking it out, it's only because the Pole or pillar box fuse has blown before the fuse inside the house, as in a 20 or 30A fuse that has been "Upgraded" to a couple of 100A. [Linked Image]