Re: Best shredder
"Shredder" is often seen as a derogatory term, because it implies they have nothing else. For pure technical modern shredding, I don't think anyone outdoes Paul Gilbert, who I do consider a shredder in a positive light. What Steve Vai does 90% of the time is not shredding, but (mostly) brilliant Vai weirdness. On DLR's albums, especially Skycraper, Vai was at the height of his shredder period as a hired gun. For neoclassical shredding, Yngwie stands alone in terms of vision, compositions, and tone, although he hasn't progressed creatively much past around Fire and Ice. Still, the best of his best is freakin' legendary!
Nuno is a genius and very tasty, and also not a shredder. To me, Satriani has no true "rock" in him; he reminds me of someone's dad who is a very talented guitar teacher who also does commercial jingles for Sony (he allowed one of his song's to be used for this!).
EVH and SRV have no place on a list of "shredders" either. I suppose you could call Al di Meola a kind of shredder, and he is my favorite steel string acoustic "shredder" of all time! Immaculate technique and compositions....and Paco is the king of nylon strings..
Cliff's Notes: I vote Paul Gilbert.