Shanghai is quite a distance away from Beijing, so this would be a pretty long ride either way. But is the countryside soo amazing that I should take the morning train and watch it all pass by on my way to Shanghai, or should I just take the red-eye and sleep my way from Beijing?
I cant say the countryside is amazing, but it's interesting seeing views transform from cold Northern China to Southern China, and from big cities downtown to cuontryside. 5~6 hours by train is ok for people at day time. If travel at night, by slow train. It takes about 11~14 hours, and it's tiring.
I suggest to take Beijing-Shanghai high-speed railway, see below for train information:
Beijing-Shanghai 1318kl Total about 5.5 hours
first class: RMB935, Second class: RMB555
first train from 7:00am, last train 17:39pm
2~4 trains per hours about 5 years ago