Really? I found GH:M to be the least useful for working on techniques.
Mostly due to the fact that every single Metallica song is the same thrash beat. And the only ones that really do anything different are Blood and Thunder, Stone Cold Crazy and Beautiful Mourning.
I'd say for limb independence and so on, GH 5 would be a good choice.
(21st century schizoid man, and scatterbrain will make you their bitch though)
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1st place on 8 GH:WoR songs on Expert+ drums! (well, at least for a couple days).
XBL Gamertag: Gavesit
Add me if you wanna play RB 3, GH:WoR, GTA IV, Halo Reach, Left 4 Dead etc. etc.
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