Ah, my bad on the dark hold.
Samus also posesses a weapon that functions similar to a black hole. While it doesn't exactly put supernovas to shame, it is very powerful. It's called the Dark Burst. The way it works is that if something gets sucked into it, it gets torn apart on a molecular level and scattered into a dimension of darkness.
Also, on the subject of X's black holes, Samus has a potential counter to them. The way a black hole works is that it crushes you into a singularity with it's immense gravity. However, Samus has something called the gravity suit which nullifies all abnormal gravity she gets exposed to.
And since this thread gives these two
everything, Samus has her Hyper Mode, which enfuses her with phazon. In this, she can shoot incredibly powerful beams capable of corrupting and corroding her oponents. On top of that, she if effectively indestructible in this form as all attack only add power to her. While this is only a temporairy boost, she is capable of continuing to put it on over and over again.
Speed alone isn't really a deciding factor. While X may be faster than Samus, Samus has better coverage with her weponry. For example, she has her power bombs which effectively function as a "kill everything on screen" attack. And there's also her ice beam which is capable of
freezing the su . I don't recall X having any special resistance to getting frozen (correct me if I'm wong).
In other words, this match is
close. Like,
really close. It all depends on who can unleash their deadliest attacks first. I think Samus is capable of pulling through if she times her Hyper Mode and ice beam correctly. But to be fair, I think we need input from more people for a conclusive answer.