Peter's said that it doesn't matter how complicated a solo is, it's how it sounds. He said he worshipped Kirk Hammett's guitar playing when he was first learning (as did I), but after you play for a while, you find it's all about style, and complexity with speed and such has little to do with good music, it just sounds kool. I play and teach some guitar, I've been playing for five years straight, and for the first three I played six hours a day; during that time all I learned was solo's and more solo's. The more experienced good guitarists I know, including myself, find ourselves not exactly playing solo's after 5+ years, instead we find ourselves playing rhythms. Solo's are great, but they are hardly what make-up the definition of good music.
A quote of Peter I can remember close to saying, "It's better to play one good note, than a lot of fast ones". And he's right.