I'm not sure how true that is but I have a suspicion that OS versions have more pressings of the limited/first presses than Japan. I thought I've seen the glitter cases and non-glitter cases of "ayu-mi-x II" OS versions and I know that the OS "Free & Easy" has the first pressing and regular pressings (when I saw these two F&E singles in Taiwan, the first press which I bought cost a little more).

As for OS CD+DVD's, they do have the CD only versions available.