Stochastic well formed colored nets (SWN) make it possible to apply performance evaluation techniques on a compact representation of the reachability graph (RG), called the Symbolic RG (SRG). The Extended SRG (ESRG) has been proposed to achieve a higher degree of reduction when applied to partially symmetric SWN models. The price to pay for the more effective state space reduction, is a loss of information on the paths of the graph. Despite this loss, it has been shown that several qualitative properties can be studied on the ESRG. We consider the possibility of using the ESRG for performance evaluation purposes and more specifically, we explore how the ergodicity of the system can be decided on this graph.