What about the guy who would be regarded as the best ever had he not contracted ALS......JASON F'N BECKER!
No doubt Satriani is incredible and I love his work immensely. His newer stuff with Chickenfoot just plain rocks.
That said, (opinion only) Vai exceeded his teacher. They are both like greased lightning speedwise, but to me, Vai has alot of emotion and experimentalism in his playing where Satch is more straight traditional style playing amped up to 12 with occasional forays into beautiful strangeness.
I could (and do) listen to both for hours. And the G3 vids? Heaven!
Becker is one of the great tragedies in the guitar world. He and Marty Friedman together were wild. ALS ended what could have been a career for the ages.
Marty Friedman - Cheer Girl Rampage http://www.youtube.com/watch?v=2iDx2E-lxbY
And don’t forget Shawn Lane....