ComfortablyNumb
Unquestionable Presence
I would have to go with Randy Rhoads but only by a hair. I saw Rhoads on the Blizzard of Oz tour and Eddie Van Halen on the Fair Warning tour. Randy, I thought was a little more tighter than Eddie. That being said, I'm not a guitarist and with that I basically don't know what I'm talking about.
You are a lucky person to have seen them both haha.
I find Randy to be the tighter player. EVH is sloppy sometimes. He never progressed much after their first album.
Randy was about learning new things all the time. He would seek out guitar teachers in each place they played and would get lessons from them.