TGV in France, Meglev train in China, and the Taiwan High Speed Rail, but never Shingansen in Japan. Again, train is the best transportation system for traveling in Japan. We bought JR East 3-day unlimited pass for only JPY10,000. We took Narita Express from airport to Tokyo, Tokyo to Karuizawa by Nagano Shingansen, then to Nagono, and back to Tokyo, and finally back to airport. That is really a super deal, and only for foreign visitors.
JR Shingansen has a very outstanding service record; safe, fast and on time. There are many types of Shingansen, and the one for Nagano is not one of the recent model, so I didn't feel it was comfortable as Taiwan High Speed Rail. Anyway, it delivered the service quality as usual. I would like to try other lines if I have the chance.