The leading model for the Gamma-ray burst (GRB) emission is the fireball shock scenario. The collisions of fireball shells with the external medium produce the afterglow emission, which is explained by a non-thermal synchrotron radiation. This work demonstrates the scientific interpretations of the multi-wavelength datasets obtained by GROND and Swift/XRT for the afterglows of GRBs 080413B, 091127 and 091029, and shows the increasing difficulties of the fireball shock scenario to model the well-sampled multi-color afterglows observed with the latest generation of GRB instruments