Good for you,you will love it.We stayed in the city of New Plymouth,which is close to
Mt Taranaki area.Beach around that area has black sand due to the volcano eruption, of Mt Taranaki.I have a brother living in Auckland,he's been there from 1968.TAG took a bit of a hit today,but nothing serious.Still keeping my powder dry...Nat gas vehicles are quite popular there,no problem filling your tank with it. Enjoy your trip,cheers