I don't know, comicfan is making me a believer on Vertigo. He's beaten top tiers like Superman before, so I think it's whoever gets the first attack off first.
Even if he does, the nature of being disorientated by vertigo is to do with the balance in your inner ear - which Graviton, after the initial attack, could simply negate, right?
Graviton wins, he operates on a much higher level.
That said if Vertigo can manage to get an attack first he should be able to dissorient and pin Graviton down, but any omnidirectional blast from Graviton as a response should take Vertigo out.
Count Vertigo's power can mess anyone up but I believe Graviton can omni blast before he looses consciousness and end Vertigo, due to his human durability.
See, this is what I was thinking. The real issue imo is Vertigo could cripple or "beat" Grav down, but Grav (even in a state that would make the worst hangover seem small) could attack without having to pinpoint. And Grav is more lethal. He takes the win, but not without a splitting headache.
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