Hi, when I had my 518 (with Meridian 500 transport and 563 DAC), I matched the output bits to my DAC (24) and found Shapes A and E to sound the best for my tastes. I found each shape had a different sound, and sometimes the recording I was playing sounded better with a different shape. You can really drive yourself crazy with this piece, but I absolutely loved it and settled on Shape A for most of my listening.
Sarah
Sarah