I emailed Codejunkies and asked if the firmware updates on Wii games that are unavoidable will brick the Wii. This is their reply:
"Further to your email on every occasion that the product is used when the disc is inserted in the console that it allows the usage of an imported Wii game disc and disables the console from been able to update its firmware, if the disc is removed after been inserted and reinserted this will again enable the console to update its firmware but still allow the usage of the imported Wii game disc. We can not advice you on the name of any retailers which may sell the product in New Zealand but New Zealand should be selectable as a shipping location on our EUR website in the very near future once we have renegotiated shipping charges with our couriers.
Regards
Daniel Leese
Technical Support"
So once you put in the freeloader, it blocks updates from the disc you put in afterwards.
Now, does anyone know somewhere that sells the Wii Freelodaer and ships to Australia/New Zealand...?