Don't take me wrong: "Rock Brasília" does deliver a nice overview of the so-called "golden era" produced by bands from Brazil's capital during the 80s and 90s. It features some great interviews (especially those with Legião Urbana's Dado Villa-Lobos and Capital Inicial's Fê Lemos) and few but invaluable footage from old shows. Nonetheless, it lacks structure and rhythm, not to mention more recent interviews (which might be explained by a lack of support). Four characters leads the narrative: the before mentioned Villa-Lobos and Lemos and Plebe Rude's Philippe Seabra plus Legião Urbana's frontman and soul Renato Russo (mostly through a single interview). It is enough for telling the overall story, but not to really contextualize much of it. Plus the director's interventions are sometimes kind of harsh and really unnecessary. Finally, for a rock documentary, though it might be said that the focus is on the phenomena itself, this film does lack more music. Most of the songs that could be mentioned as symbols of that era are played in snippets - if at all.
If you live any part of this era, you will probably enjoy the film to some extent and probably be moved by it, but I doubt that any serious listener or social observer will be completely taken by it. It does fill a still empty space. However I can't consider this anything close to a definitive portrait of Brazilian (and Brasília) rock.