Steve Vai, to great extent, was a student of Frank Zappa. It was a theme I followed after listening to the cuts Lvnthehd posted. A lot of people don't realize how great a guitar player Zappa was.
Vai, Satriani, Malmsteen etc., filled a void that needed filling. Such as when an Eddie VanHalen were a bit too stingy with their solos. Not really with regard to how the layout of a song goes, but when I just wanted to hear more of it. These guys could cure all what ails in that department, without just shredding. Then there's Vai's and Satriani's association in the beginning. Their bringing Ibanez guitars to that front as well.
I recall when Surfing with the Alien came out. I was out in Longmont, CO., hanging piecework drywall and restoring a vintage Bronco for my journey home to FL. It was about 11pm and I was wet sanding thousands of tiny pits out of the grill from where the truck had followed salt spreaders through the mountains at one point. I had almost no fingerprints left and raspberries on my fingertips which were quite sore. That song came on and I was blown away. I actually thought it was VanHalen. Got back to FL. and promptly bought that cd.
Some days, I just want to hear great rockin guitar like that. Not just the shredding that is all the rage these days.