I think TransferWise is the best service for sending money out of Japan recently. They have a modern web interface and the rates are very reasonable. I've used them myself to send money to the UK and the proces was very smooth.
Check out RetireJapan's review:
- The website is in English, it's simple and easy to use, and everything can be done online easily.
- The fee is low and the exchange rate is as good as you are going to get (they use the interbank rate).
- Setting up new beneficiaries can be done online in minutes, and the site remembers information from previous transfers so sending money to the same person takes seconds to set up.