Hello RegR,
With defence equipment and stores now being largely moved in some form of containerization or in boxed form, we are really only talking about protecting the human element in the supply chain against blasts and small arms fire during transport and to therefore use expensive platforms such as Copperhead or similar to do this simply does not make sense.
The Copperhead may provide a tad more protection against blasts for a containerized load but this argument also does not really count for much if you consider how the (protected) convoys have been ambushed and attacked along the routes through Pakistan to Afghanistan and the containers either destroyed by fire or broken open and looted. As long as the crews are protected against small arms fire and blasts, that is really all that matters and for that you do not need Copperhead type platforms at all for most of the the material being transported.
And I have left the best for last.
Once the Copperhead type vehicles have been subjected to blasts, you can rest assured they are:
(1) very expensive to repair
(2) in many instances so seriously mechanically damaged that major (and expensive) mechanical "surgery" is required to restore the main automotive geometry even close to that of the original vehicle. There is frequently major distortion and displacement of the hull and hull elements,suspension systems as well as many of the automotive components and systems such as the engine mounting system and cooling system that it is almost not even worth the trouble to repair them.
(3) a dedicated cargo platform such as the Copperhead is often out of service for months for rebuilding or repair after a major blast whilst with a (far cheaper) truck with an armoured capsule it is cheaper to scrap the vehicle and simply replace it with another or re-use the crew capsule which can very often be re-mounted on another similar base truck.
As far as the NZLAV is concerned I cannot really comment because its suitability or otherwise is determined by the NZ Defence and NZ Foreign Policies, but it is interesting that very few Armies other than NZ and the US have adopted this vehicle.
I believe totally new and more suitable paltforms are required and which can be developed at short notice.
Also, I believe we are going to see much shorter and far more cost effective vehicle development programmes in future as goverments around the globe are forced to start cutting defence spending and reduce the unacceptable levels of waste associated with so many defence programmes in the past. And Defence procurement authorities everywhere will have to lift their game very significantly too to assist in reducing costs and keeping development times to realistic levels.