Like many others Paul Gilbert...not because he is amazing, he is, but because he is also an amazing teacher (watch anyone of his videos).  Teaching is a lot harder than it looks and I have a feeling that a lot of my personal favorites (Yngwie/Schenker), don't really know what they're doing, as they've never taught, so the lessons would go: "I guess I do this, well, maybe this, hmm, let me see".