We may finally get to try out United's new flat-bed Business Class seats on the Tokyo-Bangkok leg of our outbound trip today. We've tried Lufthansa's lie-flat product twice and enjoyed it. United frequent flyers on balance think the UA "suites" are even better, but they've been a long time rolling them out. Check the starting date of this Flyertalk thread.
We'll be ready to lie flat at that point, since our three flights SEA-SFO-NRT-BKK* total 8668 miles, and our scheduled arrival is 11:45 p.m. Bangkok time tomorrow.
*Seattle-San Francisco-Tokyo (Narita Airport)-Bangkok