Transfer from Ueno to Keisei Ueno will cost a longer time with luggage if you don't know the way in advance. : are there English directions at the stations?
I suppose you don't have to worry about that as to Shinjuku, Nippori and Kinshicho; major railroad stations in and around Tokyo have directions and/or signs in English, I think.
: Can the Suica card be used?
Yes. The both routes are within Suica - PASMO area. Keep e-money of your Suica card enough for the fares.
When is your plane scheduled to leave? Are you going to the airport on a weekday? (There will be no national holiday before 21 September 2009).
I can not say for the present which of the two routes sounds better.
In Shinjuku Sta., trains are scheduled to leave
from Track 15 for Nippori route,
from Track 13 for Kinshicho route.
It depends on ticket gates how easy you can catch your train.
: are the transfers at Kinshicho or Nippori easy to do?
: Do you have a layout of the stations?
- Nippori Sta. of JR-East: Guide map
http://www.jreast.co.jp/e/stations/e1184.html
Your train comes from the north (from the right on this map) into Track 10.
On the north half of the platform, there are escalators, a stare and an elevator for you to go up.
Advancing on the pathway, getting through Transfer Gate, you find an escalator and an elevator to go down to a Keisei platform.
- Kinshicho Sta. of JR-East: Guide map (in Japanese):
http://www.jreast.co.jp/estation/stations/609.html
Your train comes from the west (from the left on this map) into Track 2.
On the west half of the platform, there are escalators, stares and an elevator for you to go down.
Advancing on the pathway, going up to the neighboring platform, you get to Track 4 where you wait for a Rapid Airport Narita.
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