I have a rather modest home cinema set up. Panasonic 37PX80, Tompson SkyHD box, Sony 350 blu ray player. The Audio side consists of a Panasonic SA PT 560 all in one home cinema system which came bundled with the TV. I have replaced the supplied Panasonic speakers with a couple of old Wharfedale floor standers, and a Q Acoustics 1000 centre speaker. This gives me a reasonably listenable 5.1 system. The Sky box is connected to the TV via a Chord Active HDMI cable and to the reciever via optical. On the 2 or 3 occasions a month that I watch a blu ray I swap the HDMI and optical cables over. Would the addition of a 4 way mains conditioning cable make a difference to either the audio or visual elements of my setup, or are the benefits only noticeable on higher end systems.