@TheCrystalShip:
I usually say, "Admiral > Shichibukai".
However, you may have a point. Battles in One Piece, are often decided by situational circumstance. While Kizaru seems to be more powerful than Mihawk by virtue of his Pika Pika no Mi, which he used to take out four Supernovae at once… Mihawk is clearly the better SWORDSman, because that's what he's trained in for his entire life: Ittoryu. Moreover, Mihawk isn't dependent on a Logia fruit for his battle prowess, so he can't be as easily nullified by CoA.
Notice also that Kizaru got his lighsaber action on because Rayeligh was using a sword. I doubt it was out of some gentlemanly notion, if anything it was because without a sword he would be at even greater disadvantage against Rayleigh.
Mind, it is Mihawk that is considered worlds top swordsman, not Rayleigh, so draw your own conclusions.
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@YouDNewb:
Yeah but look at the technique he used when Rayleigh cut him, he has to project the light off "mirrors" to where he wants to go and then he seems to move in small little beads not all at once so thats how Rayleigh had time to cut him. The same as how Whitebeard was able to stop him in the war.
Exactly my point, so this whole "he's most powerful because he moves at speed of light" argument doesn't have a leg to stand on.