We measure the aggregation kinetics of model, aqueous polymer latices of varying particle size as a function of added NaCl using dynamic light scattering to evaluate the available theoretical models for predicting the aggregation rate (stability ratio) and critical coagulation concentration (CCC). Our focus is on dilute colloidal suspensions of fixed surface chemistry but varying particle size. A master curve for the growth of the aggregate size is observed, with an intermediate regime that follows predictions for diffusion-limited cluster-cluster aggregation. Theoretical predictions based on DLVO theory are found to be in quantitative agreement for all but the largest particle size, when the particle surface potentials are determined by matching the experimentally determined CCCs. Thus, we conclude that for sufficiently smooth, nearly monodisperse particles such as those investigated here, DLVO theory can provide accurate predictions of colloidal stability for the range of parameters explored here down to truly atomic dimensions. The particle potential determined from phase analysis light scattering measurements of the zeta potential overpredicted colloidal stability but can be brought into agreement by assigning a Stern layer thickness equal to the hydrodynamic size of the counterion.