Thaksins Love Child said:Such a general question - greatest in what sense?
In terms of "shredding" and overall technique then Vai or Malmsteen for me.
Now your talking.....
and Tony MacAlpine, Vinnie Moore, John Petrucci.
Unfortunately people will always vote for Clapton, Hendrix, Bolan (lol) even Hank Marvin. But they are still great in their own right.....