Kyanar:Elpie: Although now that NZ Post has bought DHL that 2-4 days is likely to be 2-4 weeks.
Er, only just noticed this. NZ Post has not bought DHL - they couldn't afford to if they wanted to. They partner with DHL locally as part of their Express Couriers venture, but ultimately until it hits NZ it's still DHL which apart from the occasional hiccup is pretty good.
You're both right...
NZ Post have bought out the 50% share of the Parcel delivery business it had with DHL in NZ and Australia. NZ post did this because more folk are using Trademe/ebay/Amazon (the internet) to purchase online, so the parcel delivery business is growing whilst the mail delivery business is slowing.
DHL, which is Globally huge, are happy to maintain the relationship as they still retain the international transit and delivery side of the parcel business, without worrying about the local courier fleets in OZ and NZ.
Back to the topic....

