I have been using Asics for a while. I really like the support for my slightly wide foot. However, the regular hard court version did not give me the traction I need on clay, and I strained my knee last summer. I believe this is related because I recently bought this clay court shoe, and immediately felt more secure with my footing. In addition the upper shoe sheds the dirt better (less mesh), and the herringbone sole also doesn't cake up (no need to whack the racket unless you enjoy the ritual). In short, a well-thought out version of an already excellent shoe. I will just use it for clay as I have both versions of shoe.