I agree with other reviewers: The interview parts, even with the two initiators at the beginning, are really beautiful and a must-see for every Bud-Spencer-Fan. You get a lot of interesting facts and hear many adorable anecdotes not only about Bud himself but about so many other participants like co-actors, composers and directors. It was an eye-opener to me hearing that the Spencer- and Hill-movies were a reaction to the over the top violence in italian westerns. I had to smile because I remember my grandparents disliking Bud Spencer because they found his movies were too violent. XD The cut and presentation are finely done.
I wished they had left it at that and not tried so hard to put a fake story with amateur actors into this piece of work. I don't like fake stories in documentaries anyway. But this one is just awkward, and that is what makes me sad. Because the two guys behind the story seem to be really nice and they really seem to believe in what they were doing there. Their background-stories about their connection to Bud Spencer is just heartwarming. But the screenplay and acting are terrible, you can't gloss over it.
I wished they had put some more interviews with the creators into the movie, like a little making-of as part of the documentation itself. Just like in their first appearence. I guess this would have worked much better.
Still, I don't regret to have seen "Sie nannten ihn Spencer", it was a pleasure.^^