I am with Matt there, whilst it is a pain to do two yearly hydro's there is still issues with tank construction which has seen accidents in the industry.
In NZ there is also many tanks over 15 years old in circulation.
This means that the level of comfort for the tank testers is such that ..
Until all of the older tanks are out of circulation, it is unlikely the rules will change.
The biggest worry will be how will we deal with tanks imported from china which do not have the same pressure rating as those we currently use.
(Do a search on alibaba for dive tanks.. It's only a matter of time before someone starts importing them).
I cant think of anything more relaxing, than being in the downunder, breathing some nice clean fresh filtered 21% nitrox.