Currently on the West Coast at Lake Brunner and not I nor any of the other people at our house are able to get 4g reception.
The bach we're staying at is near Iveagh Bay. Sparks coverage map suggests there should be decent 4g 700mhz reception and going by gis.geek.nz, the tower I roughly s 3km away.
I wouldn't normally mind except for the fact that there's barely any 3g reception meaning you have to go out onto the deck if you want to send a text :/
edit: I should at that I tested on multiple devices (iPhone 6s,7,galaxy note4 and xperia xa, none of which could get any signal in any area with supposedly 'good' reception.