It would probably be easier to say what isn't a good brand!

But in all honesty, it really depends on the types of wine you want to buy, then look at the regions rather than the brands.

Sauvignon Blanc - Marlborough, and only Marlborough
Pinot Noir - Central Otago is the best but Martinborough also known for it
Merlot or Chardonnay - I think Hawkes Bay is the best for these wines.

I do have a couple of favourite brands but don't stick to them and will often try different wines based on supermarket specials. Also New World often has tastings so you can try things out. And City Market (in the Chaffers Dock atrium) on a Sunday morning regularly has a winery doing tastings.

For what it's worth, my favourite brands are:
Sav = Sacred Hill, Tohu and Cloudy Bay
Pinot Noir = Rua by Akarua

As you can tell, I'm more of a white person myself