Winnie has an interesting choice after the election if he's in the "Kingmaker role" again. Hipkins said on Kerrie Woodham's show that he's considering means testing NZ Super while Luxon is talking about raising the age.
Personally, I think Labour's approach will win more votes as theirs would only affect those with enough to get over whatever threshold they set while National's approach would affect everyone if the age of entitlement is increased. In other words, greed will win because, for most people, means testing won't affect them.... only the rich bustards.
Of course, Labour's way will go against the social contract currently in place..... people are happy to pay tax now to go to superannuants because, when they're entitled to it, those younger than them will pay for their super.