There's been heaps on here over the past year or so about the pros and cons of moving to NZ as so many people seem to be considering it but I can't get the search facility to work to do some links!! You might have better luck. Anyway, we made the move 6 years ago, to Auckland. Dh is kiwi but has no family in Auckland so we've been pretty much on our own since we arrived.
The cons.
It is a long way from home. I still miss family and old friends. We are lucky we can afford for me and the ds's to go home every 18 months but alot of people can't.
Don't come expecting it to be a mini England, it is very different, people, culture, work ethic etc etc...
All the crap of every day life still exists here, crime, politics, the recession, job security (although not on same great scale imo)
Pros
Fantastic lifestyle, we live on 11 acres 30-40mins south of Auckland with spa, pool close to beaches, town, movies, shops etc all 15 mins away.
ds2's day care fantastic. Free 20 hours day care when they turn 3. Really helps.
ds1's school, same fantastic - 20 per class with teacher aide. (imo primary schools have good reputation here senior/high school are varied and depend on where you live, catchment areas etc - not unlike UK. We're looking at private for ds's when they need High School. They're 4 and 8.
Great outdoor lifestyle. Again just my opinion but children are allowed to be children, have fun etc... It's summer here now, it's been a constant hot mid to late 20's. We're part way through the 7 week summer hols and have spent our time at the beach, swimming at home, visiting the zoo. This weekend we're off to one of the islands for a day trip and walk to the summit. We spent last weekend at the beach with friends surfing, having bbq's, playing tennis etc etc.... we just wouldn't/couldn't do all this in teh UK
Would I live here without children- definatly NO. Is it a better place for families imo definately yes.
HTH Where are you looking at moving?
PS it's very true about cold houses - rent or buy new (as long as they're not one of the leaky homes!! or you will freeze your backside off in winter)