I know this looks like a very simple and even dumb question, as it would be very easy to check the bands in the website, but it looks that there is something wrong in the specs:
Under Ultrafast LTE, Apple says that the A1522 model doesn't work in New Zealand:
In the iPhone 6 Plus - Technical Specifications, Apple says that the supported bands of the model are "1, 2, 3, 4, 5, 7, 8, 13, 17, 18, 19, 20, 25, 26, 28, 29". In the Wikipedia page (and other ones), is said that the LTE bands used in New Zealand are 3, 7, 28.
So will my A1522 iPhone 6 Plus work in New Zealand?