In this study, we conduct a systematic benchmark of five different force fields, UA, HUANG's Class II model, COMPASS, OPLS-AA, and Dreiding, for their ability to simulate the thermodynamic and transport behaviors of PDMS systems. Our findings highlight the varied performance of these models across different properties, emphasizing the importance of selecting the appropriate force field for a given application. Specifically, the united-atom (UA) model, although computationally efficient, significantly underperforms compared to the all-atom (AA) models, particularly in predicting accurate densities and transport properties. HUANG's Class II model, however, provides a closer match to experimental data, especially at 300 K, making it a more reliable choice for density predictions. Nonetheless, slight deviations are observed at higher temperatures, suggesting that further refinements may be necessary for broader temperature ranges. The OPLS-AA and COMPASS force fields, both widely used because of their flexibility across different molecular systems, show potential but also reveal some limitations. COMPASS consistently overestimates densities and its slower dynamics at lower temperatures affects the accuracy of viscosity predictions.