Pros
Great team, everyone is very friendly and understanding. All developers have a lot of freedom in choosing what to work on and how. Dev team is working hard to keep the code quality high. No quick and dirty solutions. A lot of interesting projects and opportunities to learn new languages or technologies. No hard deadlines, overtime or working on weekends. Pretty much stress-free. All Japanese national holidays are respected and there's a lengthy vacation around New Year. Japanese employees are very helpful in regards to finding apartment, helping with Japanese documents and all things related to visa/insurance/pension etc. Flexible work time. Travel expenses are covered, if you need to buy something for work, it will be covered too. Adequate compensation with plenty of opportunities for salary raises.
Cons
Would be good to have more vacation days. Sometimes the office is pretty noisy.