I took a Nozomi Shinkansen from Kyuushuu up to visit Kyoto and Osaka for a few days a few weekends ago.
These badass trains travel at around 285 KM/hr and are smoooooooth. They look awesome too!
In their 40 year history there have been ZERO fatalities due to accidents or derailments (including accidents caused by earthquakes and typhoons.) That probably makes them the SAFEST form of transportation in the world.
The inside is quite clean and comfortable too! Even for a big Westerner like me.
The only way to travel!