I am looking at B&W 603 S3 or DM 640 Is there any reason to pick one over the other?? I know the 603 is newer and went for $1000 The 640 is older and went for $1500. As a side note I am not one with the belief that newer is better because it often is not but in this case I do not know. My gut says 640 but I have not heard either. Thanks