HCA ratings, what are the tolerances?

[gectaa]

I''m looking at some stones and running dimensions through the HCA. I''m looking at H&A stones, so the HCA scores are very good. My question is; what is the difference between an HCA score of .8 and 1.3 or 1.7. I realize each of these are great scores, but is the .8 a lock to be a better performer?

 

[Garry H (Cut Nut)]

Probably better than the 1.7, the .8 likely has a better spread, but personal prefernce also comes into this.

Not all H&A's score below 2 on HCA.