lchiu7:droopanu:I thought about it, it should work all ok and end up cheaper. In theory the american version has all 3G/4G bands required for NZ.
Nevertheless, it has fewer 3G/4G bands compared to international version so coverage might be a bit wonky worldwide ...
According to GSM Arena it looks like these are the differences between the two models.
LTE band 1(2100), 2(1900), 3(1800), 4(1700/2100), 5(850), 7(2600), 8(900), 12(700), 13(700), 17(700), 18(800), 19(800), 20(800), 21(1500), 26(850), 28(700), 32(1500), 38(2600), 39(1900), 40(2300), 41(2500) - Global
LTE band 1(2100), 2(1900), 3(1800), 4(1700/2100), 5(850), 7(2600), 8(900), 12(700), 13(700), 17(700), 20(800), 25(1900), 26(850), 28(700), 29(700), 30(2300), 41(2500) - USA
Looks like Vodafone uses 4G bands 28, 3 and 7 which are covered by both models. And Spark also uses band 17(700) which is on all both models.
Which countries would using the US version reduce coverage?
Spark uses: Band 3 (1800), Band 7 (2600) and Band 28 (700) for 4G.
https://en.wikipedia.org/wiki/Spark_New_Zealand_Mobile_Network_(XT_Mobile_Network)#4G_LTE_Network