What length digital cable?

OK, at this point I'm fairly confused over what length digital cable to use. The manufacturer asserts that "shorter is better." Some Audiogon members agree, but others have put forth reasonable arguments to the contrary. What do you think?

My DAC/transport are CAL Alpha/Delta and the current digital cable is a 1/2 meter Kimber Illuminations D-60. Please weave that into the thread if possible.

Looking forward to the responses. Thanks!