A well stirred reactor model determines spatially averaged species composition in a plasma etch reactor by solving conservation equations for species, mass, and electron energy distribution function (EEDF). The reactor is characterized by a chamber volume, surface area, mass flow, pressure, power deposition, and composition of the feed gas. The well stirred reactor model is increasingly common in the literature due to its low requirement of computer resources for detailed chemical kinetics calculations. In such plasma etch models, assumptions on the EEDF, which are needed to determine reaction rate coefficients for electron impact reactions, are crucial for a prediction of steady state conditions. In this article we focus on a comparison for three different levels of sophistication with regard to the electron energy distribution function : obtaining the EEDF from a fully coupled solution of species equations and the Boltzmann equation, pre-computing and tabulating the EEDF for typical reactor conditions, and assuming a Maxwellian EEDF. The influence of these modeling assumptions on the steady state conditions of the reactor is examined by various parametric studies for a chlorine plasma. The results clearly indicate limitations of the two simplified approaches to electron kinetics. To summarize, in this article we show the feasibility of a zero-dimensional model which predicts steady state reactor conditions from a fully coupled solution of Boltzmann and species equations.