Dang, tough question! If I say my Stax Omega II is perfection, then I'd arbitrarily call HD800 on the CMA800R a 95/100. Taurus makes it a solid 90. LCD-XC on the Taurus is also a 95, and on the CMA800R it is a 90.
Of course these numbers are silly, because it really depends on a number of factors. For classical, I tend to choose the HD800 every time. For electronic music, the LCD-XC is a better choice. Poor recordings do better with the Audeze. Etc, etc. Plus there's the matter of source matching, which brings a whole new set of variables.
I wonder if you are comparing the SE to SE between the amps and headphones? If you were to do this comparison fully balanced (requiring 2 CMA800r) would your numbers change? I suspect they might.