When designing computer systems, simulation tools are used to imitate a real or proposed system. Complex, dynamic systems can be simulated without the cost and time constraints involved with real systems. Experimentation with the simulation enables the system characteristics to be rapidly explored and system performance data to be generated, so encouraging modification to improve performance. This paper details the experiences encountered when designing and building a proprietary continuous discrete-event object-oriented simulation in order to further investigate the performance of a proposed continuous-media server I/O subsystem. Previous investigations of the proposed architecture have been based upon mathematical models in order to calculate comparative performance. However, such static models do not take into account the dynamic properties of a system. A simulation tool was therefore built in order to assess quality of service under high system load conditions. The resulting simulation rapidly produced more realistic performance figures, in addition to providing a flexible simulator infrastructure for other unrelated projects.