They made a successful film of the unfilmable Cloud Atlas with Tom Hanks and Halle Berry. In many ways the narrative running through The Bone Clocks is more consistent and less confusing but Mitchell certainly packs a lot of invention, characters and different scenarios in which gives his books an epic multi-generational feel. My only reservation is that the strength of reader engagement wanes towards the end of the story which is the opposite to most reading experiences. Normally the reader starts out fairly neutral and then gets drawn into the story more avidly towards the resolution of the plot. With David Mitchell's books I've found that I think he is the best writer ever from the get go to about a third in to the book but the engagement declines as the initial characters and stories are resolved and new ones, or reincarnations, continually emerge and it starts to read like a collection of short stories. But maybe that's just my fault for reading last thing at night when I'm fatigued anyway and unable to enjoy making all the connections between different characters and story lines. After all that's what the fans of much more straightforward comic and film franchises enjoy.
