DL's D1 seats on the 359 to TYO are roomy, with nice tall and wide cabins. I've only been on UA's 787s and they are cramped. I understand the need for fuel efficiency but am skeptical that the new seats have a better footbox design, and will be more comfortable, until I actually fly in one. In fact, I suspect that pitch will be reduced for the non-studio seats. Everything that UA's done lately has made things less comfortable for tall pax e.g. the 321neo reduced pitch in F and smaller (i.e. shorter) underseat area.