Originally Posted by
MSPeconomist
Everyone seems to be able to get the 24 hour TWOV, so going into the city isn't a problem.
OP could even leave the airport briefly during the four hour connection if everything is on time that day, for example for a stroll along the Bund.
On a seven hour layover this would be a bad idea. It can take an hour to get the visa and another hour to get back through security. Planning to be at the gate an hour before take-off eats a third hour. The Maglev Train runs every 20 minutes, eating up perhaps 40 minutes waiting. It takes 8 minutes to ride between the city and the airport. While it's doable, it's rushed IMO. Granted, these are long, but realistic, time estimates, but even if everything goes right, how much time does that yield in Shanghai?
OP, if you are interested in going into Shanghai, which I did recently, call the airline and see if they will move you to a connecting flight the next day. I actually called from the SkyClub after checking in for my departure flight and they were able to move me for free. Do not attempt going in on a seven hour layover unless you enjoy a lot of rushing for a relatively small payoff.