Series capacitors (SCs) are widely used in long transmission lines to reduce the effective series impedance and increase power transfer capability. During faults, SCs are typically protected by metal-oxide varistors (MOVs) against excessive currents and overvoltages. Owing to their nonlinear voltage-current characteristic, MOVs provide a low-impedance path when a predefined voltage threshold is exceeded, thereby limiting the electrical stress on the SC. Under severe fault conditions, the SC–MOV system may also include a bypass switch that can be rapidly triggered to reduce the stress on the protection equipment. Accurate modeling of SC–MOV systems is essential for reliable power system stability assessment. Recently, the Western Electricity Coordinating Council (WECC) approved a phasor-domain transient (PDT) model based on the Goldsworthy MOV formulation. This well-established formulation has historically been used primarily for steady-state short-circuit studies. However, its application in PDT simulations has not been widely documented or systematically evaluated in the literature. This paper investigates the capabilities and limitations of the SCMOV model in PDT studies. Its performance is systematically assessed for MOV conduction and bypass operation and benchmarked against electromagnetic transient (EMT) simulations, which provide a more detailed representation of system behavior. The analysis also evaluates the impact of the SCMOV model on the simulated behavior of inverter-based resources, whose active and reactive power injections, as well as blocking behavior, are highly sensitive to large terminal voltage excursions.