Hmm, although I am not a big Metallica fan, as far as I remember songs like Master of Puppets, Battery sound pretty different from the album St. Anger.
About the Power Metal suggestion- Yeah Rhapsody's pretty good. You can also look for a side-project thing called Avantasia. They have two albums in total I believe. Hm. Power Metal. I guess things like Nightwish would be too far away from old Metallica (or even from St. Anger)... then again wouldn't there be too many synth stuff in those? I guess he is looking for something with just vocal, guitars, bass and drum kit... I don't know. Nightwish is really great though.
Btw... actually what's wrong with Iron Maiden? Talking about fast guitar... it's hard not to think of Iron Maiden (or am I being stupid now?).
(And come on, Opeth and Dream Theater are just too far away from Metallica...
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