I've had my 4500 system since they went on sale all those years ago. It's has been and still is, in daily use. I have mine in a horizontal line on a smoked glass shelf which is about 18" from the floor. Because the supports cannot be seen and all wires to and from it are hidden it looks like it is floating. Even after all these years it never fails to attract admiration from those seeing it for the first time and total shock when I tell them how old it is.
One of the best B&O investments I ever made. If/when it fails I will not hesitate to replace it with another if I can find one in as good condition.