I found it a bit 'thin'. Perhaps that was intentional as a corollary to the breakneck pace of time-dilation Mandella faced and the societal change he faced. I always felt out of place and behind as a reader, never really finding myself fully immersed in the story Haldeman was telling, always wanting to stop and see more about how things had changed. I guess the 'world building' wasn't as good as I hoped for.
The Forever Peace on the other hand seemed to painstakingly explore the build up to societal change, then ended as it was about to happen.
Either way, both frustrating books.