Personally, I would go on UA
. Depending on when you go, the flight from SFO
is sometimes offered on a 744 and at others, on a 777. I know that most UA
777s have PTVs on them (the 744s do not). If you do take UA
, try to see if you can get seated in Economy Plus, with 36 inch seat pitch, otherwise it is 31. Also, I like the food on UA
's transpacific routes.
is an airport with a new International Terminal, and it is really nice. I know that DTW
also have new International Terminals as well though. In terms of connecting from the domestic and international terminals, you will have to take the monorail and go through security, but it is only 1 tram stop.
Also, the fact that you only have to go through customs once (in each direction) would be a benefit to not stopping in Japan or Canada.
So, I think your best bet would be on UA
in terms of convenience and airports to change planes at, and I've had a good overall experience with them, but I must admit that I haven't flown on NW
in a long time, and never on an international flight, but I like Air Canada as well.