Sure... Norway, Denmark, Sweden, Finland, and Switzerland.... oh... and Iceland... in addition to New Zealand... Sorry... that's 7, not 6.Feel free to name a few others...
Runner up is Austria.
Special mention goes to Japan whom isn't on the list largely because I've never been there and so I can't say with certainty how it compares other than I've heard very very good things about the place.
Note how there is no Australia?
It's not that I don't like Australia... and... in fact, I'm Australian myself... But unless you're after some "single-young-man-work-in-the-sh*t-hole-outback-mines" get rich quick money, or are after a career move in banking, finance etc (in which case if that's what you want then you'd be much better going to London or New York), then I actually don't particularly see what is that spectacularly good that makes thousands of Kiwi's want to go live there.