well finally I have to disagree with ya buddie. It's not the amount of metal in a object, it is angle of reflectance that really makes the differance. A mirror will reflect a good radar signal if the angles are correct. Not because mirrors reflect light but because of the ultra thin coat of silver. This silver coating is thinner tha the metal inside a CD.
In another life we were, designing pieces of foil to be more efficent at confusing radar signals.
Now about the shape, a pyrmiad from ALO cd's 4 ft tall would return quite a big signal to the transmitting radar.
Try it for yourself, the CD's are free and you might have to buy some glue. Have a buddie nail you with his radar and see for yourself.
Now if you can figure out how to stow the thing let me know
