Take it from an old Asia soldier, with only seven days in each, you'll spend most of your time recovering from jet lag. If dreaming, then dream big and spend at least 10 in each and allow for travel between. NZ is much farther than you think from the RSA. The time difference is 10 hours. In the military, during deployments, we assumed a day of jet lag for every two hours of time difference. So heck, take a month off and do it right.