In recent years Thermoplastic Elastomers have became one of the fastest growing material classes used in industry and are therefore under pressure in terms of cost efficiency. Process simulation is a possible solution, insuring optimal process conditions for the material while making the process as efficient as possible. This is only practicable with reliable data depicting flow behavior. However the rheometric data for Thermoplastic Elastomers is very limited and there are few publications in the literature which contain comprehensive knowledge about their flow behavior. Like in processing, Thermoplastic Elastomers are commonly handled like thermoplastics in rheological measurements, without questioning whether the measurement conditions are valid to estimate flow properties. In this study, capillary, rotational and oscillatory rheometry were used to estimate the rheological properties of several, commercially available Thermoplastic Elastomers. By varying the method and experimental conditions, the data can be compared in terms of fulfilling the Cox-Merz rule, considering influences of the applied method which can occur due to rheological effects. The data were also evaluated in terms of validity by modeling the capillary rheometer that was used with the finite element method. The results contribute to a better understanding of the flow behavior of Thermoplastic Elastomers and reveal a dependence of rheometric data on the chosen method.