Recently several second order closure models have been proposed for closing the second moment equations, in which the velocity–pressure gradient tensor and the dissipation rate tensor are two of the most important terms. In the literature, the velocity–pressure gradient tensor is usually decomposed into a so called rapid term and a return-to-isotropy term. Models of these terms have been used in global flow calculations together with other modeled terms. However, their individual behavior in different flows has not been fully examined, because they are unmeasurable in the laboratory. Recently, the experimental data for axi-symmetric flow measurements of Ertunç (2008) (J.L. Lumley, 1975) have given us the opportunity to do this kind of study. In this article, we make direct comparisons of five representative rapid pressure strain rate models and eight return-to-isotropy models with the experimental data for axi-symmetric flow measurements of Ertunç (2008) (J.L. Lumley, 1975) and the theoretical RDT results of Sreenivasan (U. Schumann, 1977). The purpose of these direct comparisons is to explore the performance of these models at different contraction rates and identify the ones which give the best performance. The paper also describes the modeling procedure, model constraints, and the various evaluated models. The detailed results of the direct comparisons are discussed, and a few concluding remarks on turbulence models are given.