Two different rigid models of benzene, a united atom model and an all-atom model (both previously validated for vapor-liquid coexistence), are evaluated for phase behavior and stability in the condensed phases using thermodynamic integration along a pseudo-supercritical path. Both models give fairly accurate melting points from the most stable solid phase at ambient condition (with a Pbca space group) to the liquid phase. In addition, the stability of the Pbca solid structure is determined relative to the stability of the experimentally known high pressure polymorph with a P21/c symmetry. Both models reproduce the correct trend in polymorph stability as a function of pressure.