Thanks for replies.
Out of interest got an email back from EK saying 3hr at AKL is due terminal congestion and is recommeded by AKL Airport Authority.
However they also recommend 2.5 hr at BNE airport.
FYI, booked at short notice (72hr) EK were actually the cheapest fare available - $345 return + taxes. Next closest was QF (not Jet Connect part of it but the 744 service).