Don't know if votes made by the OP themselves count though....
Aside from that, i'm going with Kenshiro based on Grudge's words. Hokuto Shinken could technically still work on Superman, it'll just take Kenshiro some time to find out WHERE they are located at. Speaking of that, it'd be interesting for races like Kryptonians or Saiyans or otherwise to have pressure points and imagine Ken to be able to actually defeat one if he can manage to poke them through.....huh....hmmm....*shrugs*
If Ken can't use Hokuto Shinken (or the other Hokuto fighting styles like Soke Ken and Ryu Ken), there is the Nanto Seiken style and Gento Koken style. With Nanto Seiken, and as Grudge said above from earlier, it allows the user to destroy the enemy from the outside rather than from the inside via pressure point attacks like Hokuto Shinken. It also allows one to bypass durability and even negate Regenerationn to an extent, so Ken should be fine if his main style doesn't work out. Same for Gento Koken. It's a style that's described at being able to destroy on a cellular level so....Supe's is screwed if Ken pulls out a ki blade of energy and slices him in half with it.
That and if all else fails, Muso Tensei gets pulled out. Here Ken can't get hit due to the tech. granting him intangibility and how it allows him to bypass durability by destroying his opponents atoms so......yeah.
So it's as what Grudge had said, and my vote goes for the grandmaster of Hokuto.
