I'm one of the few barefoot/stocking-foot types at my Systema school. That's a habit from training on hard floors and mats in Hapkido and Karate. So I have some questions: What are the benefit of mat shoes for me? What will be different? Any recommendations for shoes? I'm curious about the shoe that has the pivot ball in the ball of the sole. I have access to two good suppliers right her in town, so I won't have to order online and take my chances. I welcome input form all practitioners.