Hardness is usually measured on the Rockwell scale . Harder blades will deform less, and so keep their edge longer. Edge retention is an important measure of the sharpness of a blade.
I think trying some will let you find out which work best for you (too many variables).
I find Feather, Nacet, and israel Personna to be good. And also Schick and Persona injector blades....
I think trying some will let you find out which work best for you (too many variables).
I find Feather, Nacet, and israel Personna to be good. And also Schick and Persona injector blades....