I took a couple of days in Whangarei from Blenheim recently. They are now using Bombardier Q300 aircraft out of Blenheim and into Whangarei, So much nicer than the previous small Beech 1900D's. The flights seemed smoother, not sure if it is the larger aircraft or maybe it was just calm air!! The online check in is brilliant, you can check in for your domestic flights up to 24 hours before the flight (watch out as the online check in does close 30 minutes before the flight takes off). I use the Air NZ mobile app and it is excellent, no need to print off your tickets, just use your phone.
Air NZ have also resumed the coffee/tea service on the longer flights which is really nice. Helps make the flight go quicker!!