Rough casts are not transfering in a even way like the old Paf magnets. Other say its just the looks.
Some say a shorter magnet (like the 60ies paf magnets) have lower ability to get charged with magnetic power = have lower gauss readings.
Some say its only a matter the amount of charging.
I have both rough casts and one shorter: the rough casts have lower magnetic force and i did not manage to do more (but this could also be a function of the material)
My short magnet is one of the strongest i possess!!