Two years after their commissioning, the third-generation synchrotron source are ripe for a critical analysis of their performances, based on the broad practical experience of hundreds of scientists. The most relevant questions are: can one confirm that high brightness was the best choice for the sources of this new generation? Can one actually see the impact of the high brightness level on real applications? We try to answer these questions in the specific domain of surface and interface chemistry and physics, using a series of examples, primarily provided by the ELETTRA laboratory in Italy.