I bought one VPI brick in 1988. Still have it, used it on everything that I could, and frankly never found a dfference good OR bad in the sound. It is useful for adding mass to the top of a CDP, and looks nicer than some things you could use. My advise would be to make your own box out of your favorite hardwood and fill it with lead shot or a mix of lead and sandbox sand (I say sandbox sand because it is supposed to be "sanitzed"). You'll have the same thing and will have saved yourself about 70.00, save the Websters for reading while you're listening.
VPI Magic Brick or Webster's Dictionary
Wondering: What's the difference between placing the VPI Magic Brick and Webster's Dictionary (Unabridged, of course) on top of your CD player? Would the latter give me more definition? Okay, okay, I'm sorry. Seriously, though. What would the difference be? This from the Department of Snake Oil.