I don't know what your legislative bodies are like over the ditch, but here in Oz the issues you have raised open a minefield.
Do NZ cars come with a tyre compliance placard - put on by the manufacturer ?
They do here in Oz and you must abide by the speed (H, V, Z etc ) and load (89,95 etc) ratings on the placard. If you don't and you have a prang, your insurance company can wipe you.
In Oz there is a 1 category leeway allowed but to achieve this you must get approval both from the government authority and the insurance company and get a new plate from the manufacturer. Or at least so I have been told - I have never tried it.
It might be worth giving your insurance company a ring if you are not sure, as well as your roads authority. they should be able to put you straight.
The other thing to realise is that you don't choose the speed rating on tyres with regard to how fast you drive. As I understand it, the higher the speed rating, the higher the quality of manufacture and the higher the consistency of the quality level. In other words, a Z rated tyre should have a higher quality of manufacture and there should be less variation between tyres than in an H rated tyre.
With regard to your choices, I have no experience of them but here in Oz your car would have at least a V tyre speed rating and I would suggest that that would be a minimum requirement.
I tend to prefer Michelin and Pirelli tyres to most others but it depends on what is available in your outlet. It is also worth checking where the tyres are made. In my experience a Michelin tyre made in France or Germany will be superior to one made in Brazil. (With all due respect to any Brazillians reading this).
Hopefully others on this forum can give you advice on the individual tyres that you mentioned.
Good Luck, but take some time to do your homework - it pays off.