I studied Japanese Studies in university, obsessed over the culture, and eventually spent a long summer there. I considered living there for a year, but it never worked out. However, over the years I gained a much more balanced view of Japan. Frequenting a message board of people teaching English all over the country, I learned about the good and the bad. The running joke was that some people come to Japan for "the green tea and onsens," or the superficial parts of Japan that aren't the "real" Japan.
Japan is like any other country in that what you get out of it depends on what you put in. Someone who works hard to "assimilate" will have a very different experience from someone who sticks with other foreigners. I think its different from other places in that there is a limitation to how far many people can assimilate because there is a form of cultural xenophobia that isn't found in many other places.
But jeez, if I hear another travel segment talking about Japan's unique mix of the "modern and traditional," I'm gonna puke. The same could be said of almost any country.