For transfers for more than 40,000 JPY, use Currency Online.
If the amount is less than 40,000 JPY, you’re better off using PayPal.
Currency Online would win out in all cases, except that they use an intermediate bank to get the funds from the Bank of New Zealand to any bank account in Japan. I asked COL if they had any accounts in Japan and they told me no. They said their Japanese customers always eat this fee. So no matter which bank you have an account with in Japan, you’ll be looking at receiving roughly a 2,500 yen charge.
Doing some quick math and assuming the 2,500 charge, this gave me a tipping point of 40,000 yen.
Hope that’s helpful to others out there who are trying to weight the options. If you’ve done a transfer with COL to a Japanese bank account and didn’t get charged, do let me know!