NRT is super easy IMO. Off the plane, up to security, right back down to the terminal with a short walk to either a lounge (United usually being the closest, NH farther away) or to your gate.

This week I connected in YYZ from domestic Canada to US-bound. That was a crazy walk, although well signed.

LIS is also an easy connection point.

Anyway, back on topic. I'm arriving SIN this week via UA's flight from HKG at 1220am. Hoping that immigration isn't a long wait. If they are doing the fingerprinting then it can take awhile. Although the airport is so big that baggage can take forever. Usually I'm the first through immigration from the flight and still have to wait 20 minutes for my bag after the long walk to get to immigration. Will see how it is after arriving in T2.

-RM