tweake:
i would do kiwi saver to start with.
the reason being is KS is hard to access, more importantly hard for other people to access. so many times that people setup accounts/investment for kids, and it gets cleaned out in the divorce, scammers, hacks, family members drug problem etc. or it gets cleaned out as soon as kids get access to it. this is why govt proposed opening up KS for other things so certain industries (like housing) could profit by cleaning out peoples KS accounts.
thanks, i'm not worried about it getting used, just wanting the best returns.