We describe V-SAT, a tool for performing design space exploration of System-On-Chip (SOC) architectures. The key components of V-SAT include EXPRESSION, a language for specification of the architecture, SIMPRESS, a simulator generator for analysis/evaluation of the architecture, and the V-SAT GUI front-end for easy specification and detailed analysis.We give a brief overview of the components (EXPRESSION, SIMPRESS and GUI) and, using an example DLX architecture, demonstrate V-SAT's usefulness in exploration for an embedded SOC codesign flow by specifying and evaluating several modifications to the pipeline structure of the processor. We believe that V-SAT provides a powerful environment, both for early design space exploration, as well as for the detailed design of SOC architectures.