I wish our politicians would follow suit. Now I've gone on and on about the lack of merit some of the proposed PR systems have but my one main argument has always been it gives small fringe parties too much power. IRV doesn't do that, it allows us to substantially marginalize strategic voting as well as giving us the opportunity to still vote directly for our MP. That's important to a lot of people including me.
As I've said before the vast majority of PR proponents only want PR because it will help their party gain more power. They may trot out a bunch of BS about fairness and all that but in reality it's about one thing: Power.
Now as a Liberal I of course am threatened by PR because it substantially lowers my party's chance of obtaining a majority. I freely admit that, but at the same time I can look past that and see that there are flaws in our electoral system. Strategic voting is a problem. People should vote for who they want to vote for and not have to support some candidate they don't like as much because they fear a worse candidate might win. IRV doesn't solve that problem, in fact in researching forms of proportional representation I've found that the only system that truly eliminates all strategic voting is random voting by a computer which of course isn't preferable (unless you live in Florida)
IRV is the right way to go with our current Parliamentary system, to institute true PR even with a threshold with our current system of Parliament would elevate parties that should have little influence (because the vast majority of the country voted against them) to potentially having all of the power and holding Parliament hostage.
Now PR supporters will say that the other parties can simply band together and stop this from happening. And that does sound great, except I live in the real world where my Party hates your party and vice versa.