NikT: According to that Amazon product page, it also doesn't support band 3 (1800MHz), making it useless for 4G in NZ..
Listed LTE bands: 2, 4, 5, 17 = 1900, 1700, 850, US 700MHz B block
Bands 3, 7, & 20 (1800, 2600, 800) are the important ones for European LTE, so I suspect this 'universal' business is a misnomer & the European 4G Moto G will have completely different band support. Don't buy the US 4G model, it's no more use on 4G in NZ than the existing dual SIM 3G model is.
Actually the Moto G dual SIM works fine with two Vodafone SIMs in it