I have the Furman - Elite 15PF - i - Power Conditioner and I am very happy with it. I have had the surge protector kick in once during a bad electrical storm and it saved my equipment. I am very pleased in that it does not have any sonic signature or color the music in any way. It also has a 45amp reserve for large changes in dynamics and it has 13 outlets for both audio and video gear. I have never used the Surge X, so I have no opinion on it.