RE: Where to go, how much time, etc. I really liked NZ better for cycling than OZ - if I go to OZ again, I'll rent/buy a campervan - the interesting bits are spread so far apart, with lots of flatness in between (I hate flat riding). And the drivers are less friendly than in the US. The animals were the best thing about OZ, the traffic the worst. Admittedly, I didn't go north/east of Melb, which I bet would be both more interesting and more traffic, and the continental divide mtns would be of interest.

OTOH, NZ is incredibly diverse in very short distances, and there are tons of things to do off the bike (hike, backpack, mountain bike, kayak, paraglide, bungee jump (if you like that sort of thing) ). NZ was less 'different' than the USA than OZ is, but the land forms are just amazing - and that's what I like in a tour - amazing landscapes, interesting hills, great views, challenging riding...

After 7 weeks in NZ I was bummed I had to go home. After 5 cycling (and another 6 climbing) in OZ, I was ready to go home. That might be me, not the place, so FWIW, YMMV, etc. etc.

Oh, and I would disagree with an above post characterizing the wind direction in NZ. The prevailing wind is "head" - It's strong, and changes direction 90 degrees daily, I'm not making this up.