That's an incredibly interesting one. Prince has been growing on me over the past few years. I think he has been underrated due to his showmanship, songwriting and persona. I think I'd put him in the group just below Hendrix, Clapton. Page, Allman and Jeff Beck.
I liken Prince to Pete Townshend. Each were such brilliant and innovative composers that their playing sometimes was taken for granted. They could each make more out of less than almost anyone ever. They also took music and musicianship to other levels. Each expanded the art to places people weren't expecting.
A perfect example of this was his performance at the Grammy's of While My Guitar Gently Weeps. All those great players completely deferred to Prince.
I think there are more modern people to discuss in the next group of five than in the Top 5, but I think I'd put Prince, Townshend, Van Halen, Brian May and Slash in that group. I think Gary Clark, Jr. may join at Top 10-15 soon.