i tend to prefer solid rhythm players who come up with interesting and inventive parts over shredders in general, so for me, it's guys like Andy Summers, The Edge, Johnny Marr, etc. and Prince, although he's not so well known as a guitar player as a singer, cuz he has some KILLER funk licks and solos.
as for shredders though, i love Eddie Van Halen (for his unpredictability), Vai, Greg Howe (insane jazz-fusion shredder)