The calculations of the optical characteristics of fractal aggregates find important applications in a wide spectrum of disciplines. Consequently, considerable research efforts have been invested to develop models to predict the scattering properties of aggregates. A comprehensive understanding of the accuracy of these models is highly desirable for the users. Therefore, this study assessed two commonly-used fractal scattering models, in terms of their accuracy for predicting both the integrative scattering properties (e.g., the scattering cross section) and the angular scattering properties (e.g., the elements of the Mueller scattering matrix). The results were organized as contour plots with respect to scattering angle and aggregate size to facilitate the estimation of error introduced by these models in practical applications. Meanwhile, a direct comparison and evaluation of these models was also performed, which can potentially enable a hybrid model for better accuracy. This study was conducted under the context of scattering by soot aggregates; hence, the results are expected to be directly applicable for soot characterization by laser scattering.