An increasing number of large aperture telescopes and antennas are being designed to meet a wide range of scientific objectives in both terrestrial and orbital environments. Because of the large scale of these instruments, studies have shown that materials and structures drive the design of these systems. Mass, surface figure, and overall dimensional stability are critical for most subsystems in these applications. Accordingly, light weight, low cost, structurally stiff materials are the most attractive candidates. To address these reflector technology challenges JPL has initiated directed research that has led to major technology programs whose objectives are to evaluate, advance and apply structural composite materials technologies to high precision, thermally stable, lightweight mirrors. JPL has taken a balanced, iterative approach that combines analytical simulation, hardware fabrication, and mirror performance testing. This paper will focus on the computer models, mirror performance evaluation and their correlation.