Coming to the data I was aware of a number of issues:
- Unlike most geographical data users, I'm primarily interested in the names rather than the relative positions
- New Zealand is currently going through an extended period of renaming of geographic features to their original Māori names
- The names in the dataset are primarily map labels and are subject to cartographic licence
- Names can differ only by punctuation. There is a "No. 1 Creek" and a "No 1 Creek".
- Names can differ only by presentation. There is a "Crook Burn or 8 Mile Creek", an "Eight Mile Creek or Boundary Creek" and an "Eight Mile Creek" (each in a different province).
- There is no consistent presentation of alternative names. There is "Saddle (Mangaawai) Bivouac", "Te Towaka Bay (Burnside Bay)", "Queen Charlotte Sound (Totaranui)", "Manawatawhi/Three Kings Islands", "Mount Hauruia/Bald Rock", "Crook Burn or 8 Mile Creek" and "Omere, Janus or Toby Rock"
- There is no machine-readable source of the Māori place names with macrons, and the human readable version has contains subtle difference to the machine-readable database (which contains no non-ASCII characters). For example "Franz Josef Glacier/Kā Roimata o Hine Hukatere (Glacier)" and "Franz Josef Glacier/Ka Roimata o Hine Hukatere" differ by more than the macrons. There appears to be no information on which are authoritative.