i'll agree slayer are more technically profficiant
but i'd say metallicas guitars are still more skilled in terms of musicality, they just sound nicer to the general ear
creativity though.... i think metallica have been far more versatile throughout their career, more slayer sounds the same than metallica sounds the same to me
when i was young i thought metallica were good too, but it wasn't ignorance, it was musical taste...an ever changing thing it seems
i don't listen to metallica at all anymore by the way... just not a fan anymore