I've loved Eat 'Em And Smile since the 80s, and I remember the day I bought Skyscr@per (on lp of course!) and went home and played it for the first time. I prefer his tone on EEAS and but I can't seem to get close with my own set up (or playing!):(
As for skyscr@per, it does have one of my favourite Vai tones, the intro to Two fools A Minute is awesome, so chunky but almost clean. That said I like his later tones too, There's A Fire In The House is fantastic!