Hi Karen
I am renting in Rolleston at present with my wife,Tracy and our 4 daughters. I agree with most of the earlier replies as it depends on what you want when you move to NZ.
We originally rented in Parklands while waiting for our furniture which is a nice area and house/rental prices are higher there than many areas in ChCh.
Rolleston is still a new, growing town. I work out of Hornby so I have gone from spending 90 bucks a week on fuel to 90 bucks every 2 and a bit weeks.
If you want a nice new 4 bed 2 bath house, there are plenty to choose from in Rolleston and reasonably priced, I guess, compared to suburbs nearer city centre.
It is an ideal place to buy a section and self build.
Wait till you get to NZ and check out the place, it might be what you are looking for and then again you might hate the place.