Aterpster.
175m does not deal with landing roll. Thats why you have the 50m requirement for the Cat3B.
Therefore I ask again why bother with 175m if no DH with Cat 3A ? I simply dont see how you can do a Cat3A with no decision height as this could be a fail passive approach and as such has no redundancy for the autoland.
The question of which minima to use comes initially from the individual OPS-SPEC granted to each company when approval to operate in that country/state is given. Many EU operators may wish to stay with EU minima for ease of use.