Pros
Unlike many other tech companies in Japan, SIE has its own world-famous products and services that you can be proud of as an employee. You can have your own flexible work schedule. Some days you may have an early meeting to start a day with and may finish up early. No one really bothers you with your schedule as long as you do your thing. You get to work with people working in different regions. The main offices are in California, London, and Tokyo, but there are a lot of branch offices in other places too. Working with overseas colleagues can be fun if you don't have a language barrier.
Cons
Due to the trend and size of the tech job market in Tokyo, salary here is considerably low compared to colleagues in California. The pay gap can be 2.5 to 4 times depending on the exchange rate.