Please don't take this as RW schadenfreude, but there has been much sense talked about the relative value of a small FJ force for a nation such as NZ. A couple of sqns might soothe egos and provide an interesting diversion at airshows but in the real world such a force would be hideously expensive for a nation the size of NZ.
It is not just the purchase and operating costs. The logic of some posters is that NZ FJs could be deployed in support of Coalition ops. The cost of keeping a small fleet of FJs up to Coalition Theatre Entry Standard would be horrific; even the UK struggles to keep a small proportion of its' relatively large FJ inventory at TES standard. Then the logistics cost of supporting such a det would be a large strain, possibly dictating more AT/AAR etc etc. Finally the US would say "Oh great, 6 old F-16s (for example), park them over there behind the rows of F15s, F18s, F22s and (eventually) Typhoons." To contribute SH and troops would receive a much warmer response as NZ has, pound for pound, some of the best troops on the planet.
So, stick to your (door) guns. Do what is right for NZ. Buy MPA to secure your own backyard and, if you want to support GWoT, provide more troops and Helos. The bonus of this is that the troops/helos can also be used at home or abroad in non-combat roles (SAR/Disaster relief) to provide more than just a "woosh" at airshows.