Take the money and run
Thanks for your question. As I am not an authorised financial advisor, I can not give you advice per se on what KiwiSaver fund would be best for you given your short time frame for investment. As you are probably already aware, you are entitled to withdraw your funds if you leave the country permanently although you'll
ime in New Zealand will be briefly.
I am assuming that you have New Zealand residency and are thus able to qualify for KiwiSaver. Leaving the country permanently is not an obstacle to retrieving your funds but you do have to provide documentary evidence of that.