I flew the 787 2 weeks ago with NH, SEA-NRT in C and I loved it. Definitely noticed the higher humidity levels and did not feel dried out, either skin or eyes, at all. And I normally really suffer from dry eyes. Much quieter than any other aircraft and the huge windows are fantastic. We had zero jet lag when we arrived in Japan and I firmly believe it was because of the 787.
It's my favorite aircraft as of now and I will go out of my way to fly it from now on if at all possible. Especially in C