in case any one is interested the chrome stands up alright under the conditions, here is a pic after 700KM of use.

If they are DBA rotors, they will have the " Kangaroo paw " pattern on the vanes, therefore, they are not directional for the vane part, but they do have different part numbers for left and right.

DBA rotors for Ford only have kangaroo paw in the 4000 series and up.
The stocker slotted and/or drilled rotors have straight vanes.