I can't compare any english universities with Japanese ones teaching Game Technology, but I hope you are aware that your Japanese has to be very fluent to get accepted in any university in Japan.
I also think that there are alot of students in this particular study in Japan and only the best will probably make it. If your Japanese is fluent and you have good skills in what you do, you may also make it ofcourse in Japan. But I have the feeling that any Game design company in Japan would be more interested in hiring foreign people (fluent Japanese) that have studied in Europe or the USA, only because they have a different background and they could create more depth in the designing of games.