well, IMO Mikael is an outstanding guitar players, he hasn't studied guitar, but his technique is unique, but the fact is that he doesn't brag when he is soloing, he just plays from his heart, and to me, that's something that appreciate, there's many technical/virtues guitar players, but there's only a few that can touch heart through a guitar melody, and again, i appreciate that a million times more than the technical way.
Peter, to me, is equally gifted as Mikael is, the way that he sees the music is as good as Mikael's way, his solo in Wreath is awesome. Technically they are great, but the most important part is that they can reach my heart though Opeth's music, and to me, that's unpayable.