I've heard plenty of remixes of songs off DM and heard them live. Though I think Thrash metal is one of the more primitive, repetitive forms of "heavy" music Metallica's takes on it really caught my ear, Master of Puppets and all that.
I really enjoyed their 90s stuff as their writing really took a step forward, sure it wasn't "metal" but that's just chug chug "frash" fanboy tears talking, Load had songs like Bleeding Me and Outlaw Torn, Reload had songs like Fixxer, Low Man's Lyric and DEVIL'S DANCE! Its not ALL Doom and Gloom for Metallica.