How common was the later revision (small saucer fires immediately when it appears, and can aim at you across the wrap around) compared to the original? MAME ma

How common was the later revision (small saucer fires immediately when it appears, and can aim at you across the wrap around) compared to the original? MAME makes the newest revision the 'default' (in terms of their ROM naming) so I sometimes feel like that's the one I 'ought' to play but it's very much harder than the original, which I enjoy more (while currently I'm not good enough to deliberately 'hunt' the saucers anyway).