In this paper we present a study of the impact of avatar realism on user experience and performance in stressful immersive virtual environments. We evaluated a stressful and a stress-free environment with partial avatar embodiment under low (iconic) or high (photorealistic) visual fidelity conditions. An experiment with forty participants did not reveal any significant differences between both graphical versions. This first result represents an interesting finding since non realistic avatar and environment representations are faster and more economical to produce while requiring less computational resources.