Thanks, you're right, all letters are present. I have chosen Z: as default VSS drive. If I may insist on something, it would be nice if the installation of a new version could preserve the settings of the former one, when applicable. Maybe it's already the case, all the better !
Regarding VSS, or Fallback, it seems to me that now you consider VSS as the Fallback method, which is indeed faster and apparently safer. I also remember that you indicated VSS was the best method in previous versions.