Rubber toughened Styrenics represent an interesting model system for a blend containing a soft second phase in the form of dispersed spherical particles. The elastic properties of such a system have been widely examined in the past, both from experimental and theoretical viewpoints, however some questions remain unanswered. In this work an attempt is made to rationalize the field via the proposal of pertinent experimentation followed by a short review and the application of a convincing theoretical model. The elastic properties of rubber toughened Styrenics appear to be reproduced by a diluted model for spherical inclusions, in which the lower bound condition has to be used to describe the elastic properties of the second phase particles. Also, the more phenomenological Nielsen equation closely reproduces the experimental data. These results suggest that the role of stress intensification around the particles in rubber toughened Styrenics has to be reconsidered.