I own a Hitachi 42pd5200 alis panel> I am considering an upgrade. I have witnessed during my one year ownership of this plasma a variety of artifacts including noise on back ground surfaces [interior walls etc] and false contouring. I am using a denon 2910 hdmi to dvi cable. Which plasma is the best out of panasonic or pioneer with least artifacts with sd discs and absolute minimal false contouring? [the most annoying to me] I don't mind upgrading to a hd model from either of these manufacturers. any panasonic or pioneer owners out there who can advise on the picture gremlins listed above?