I think that Japan is a very interesting place, it's culture is very different from those of other Asian countries. So if I were to study abroad there, I would wanna stay for a longer period of time to get the full experience
Japan economy is dropping continuously in this 15 years. Korea is out performing Japan already. Living in japan won't provide you or your kids any good. I cannot see Japan is good to dominate the world's technology or electronics again.
Japan is a country that well protect (or too protect) to its own culture and language. Their currency stays very very high even at its recession. Chinese like us staying there will have harder time to become successful. They are too protective to their own group and seniority is their deadly wound.
Any if you were scare of getting cancer in your early 40s, try staying there for a longer time. Radiation is spread out like virus everyday. I saw many foregin students and workers flee back to their own countries after the nuclear leak. So why going back to there to being X-ray hundreds time a day.