Another expat here, lived in Yorkshire for many a year m'sen but escaped here from the South East getting on 6 years ago.
The people may be friendlier than you're used to if you move here from south-east England to anywhere outside Auckland, but I loved Yorkshire and Auckland is nowhere near as friendly on the whole (KB excepted) as the original God's Own County, nor the rest of NZ. Auckland is also a relatively expensive place to get a house.
The driving approach is a lot less co-operative in NZ generally than in Britain with more aggression overall. If the UK population drove like they do here, there would be constant gridlock and blood-letting. Luckily outside greater Auckland they're aren't many people to muck things up.
Also, if you're a gay vegetarian, stay in Britain as you will feel a complete outsider everywhere except Ponsonby (AKL suburb).
Otherwise get over here because, minor niggles aside, this is a fabulous place to live. I won't be going back and they can't even kick me out now as I have citizenship.
And if you fancy a bit of dual sport / ADV riding, this is a bloody good place for it. And that's just on the main highways...
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