[samurai007]

It doesn't need to be either/or. You could do both Temple and JET. The rules for JET say you must not have lived in Japan for 6 or more years in total since 2000. So you could do Temple, graduate from university, and then apply for JET.

Temple you'd have to pay for, and I believe it isn't cheap, plus living expenses. Student visas allow only very little part time work, so you wouldn't be able to pay for it with a job while you are there. JET, on the other hand, pays quite well (3.6 million yen per year). JET can be very hard to get in to though... on the best years the success rate is only about 25% of applicants, and with the economy as it is (more applicants, more current JETs recontracting so fewer spaces for new JETS), that has fallen to about 18% I've heard. Even excellent credentials are no guarantee of being accepted. Finally, if you are accepted on JET, remember that your job will be to teach English and western culture, not to practice your Japanese. You'll pick it up just by living there of course, and can take a class outside of work hours or trade English/Japanese lessons, but it's not the same intense study of grammar and words and such as a university-level course.

So, I'd say go for both, they are quite different experiences and each has its benefits and drawbacks for what you want.