UA beats NZ hands down, and don't forget DEQM offer (if she booked and paid for her ticket after 15 March, and completes travel before 15 June) - one roundtrip SYD-LAX and voila she's Premier = Star Alliance Silver - which takes much longer and much much more $$$ to be Silver with Airpoints.

Depends how often, how far and how keen she travels, she might want to do a couple MRs to be Premier Executive with United (Star Alliance Gold), or Air Canada, or bmi; I think these three airlines' programs are top 3 of the Star ones and any of these is better than Airpoints.

BD for value of its miles, AC for the ease of becoming and renewing Star Gold, and UA for 100% bonus miles and e500 upgrades when you are Premier Executive and 1K.

Cheers