depends what you want
NZ, awesome touring and hiking, great backcountry terrain wise (not nec snow wize), great parks, great nightlife, beautiful country, cheap heliskiing
Aus, pretty flat, almost every afternoon is a slushfest, pretty good parks, more expensive, tree skiing!
I live in Australia btw and have skied NZ the last 3 winters with the odd week in perisher/buller
planning on buller this year though