This has been around for a while, I finally booked mine not too long ago. I didn't post it as a MR since it looked to me like a long DOJ as opposed to an MR ...
You have to work a little to find the dates that work and in some cases force an overnight in TYO for the lower price.
If you book NH metal, the lower fares book into K class, 100% PQM on UA but 25% RDM. Changing dates and departure/arrival cities will in many cases add on another $100 or so but will book into L fare for that leg (50% RDM). Both of course better than the scant few RDM you'll get on UA metal.
D.
http://www.momondo.com/flightsearch/...false&NA=false