Which colour difference equation should I use?

It is established that the CIELAB colour difference equation is inadequate for many purposes - equal sizes of DE* correspond to different perceptual differences in colour. There is strong evidence to show that most of the modern optimized equations (such as CMC, M&S, BFD, and CIE 94) are more uniform than CIELAB. It is not clear, however, whether any one of these new equations is significantly better than the others. The CMC equation is a British Standard (BS 6923) and is being considered as an ISO standard.