Hi. In all honesty I'm not sure. My impression is that although the recession doesn't seem as bad here as in the UK, it is a reality and I know people who have lost their jobs so I guess it would depend on what work you and your dh would be looking for, where your parents live and what the job prospects are in that area. Having said that they say the economy and job prospects will improve by the end of the year. Dh is in construction, which has certainly been hit but not as badly as the UK and his company is turning work away and employing new people to keep up with the work that they have. The man next door, also in construction, has gone bankrupt at the mercy of a debtor who couldn't pay!
In terms of day to day living NZ prices look good when you convert pound to dollar but once you start living by the NZ dollar (which I always recommend from the minute you get off the plane, don't convert) it's definitely not cheap. Housing, basic food, books, clothes, shoes all expensive imo. There's also benefit which I assume you would be entitled to in the UK but not sure whether you would get here???
Maybe look at salaries for your dh's profession, check out foodtown or woolworth for food prices, and some other on-line shops for ideas for prices, rentals in the area you're looking at moving too (unless you're going to stay with your parents etc).
That's probably not much help. I guess I would say come because you want to rather than because you think it might be cheaper to live here, I'm not sure it would be but don't know for sure!