Heavy
One thing that really makes this one better than the other RB/GH games is the band itself. Metallica is huge and pretty much everyone has heard a lot of these songs so It's easier to get a singer on this than, for example, some pretty much unknown alternative pop or spanish stuff. Also this has all the instruments whereas the Aerosmith version had only guitar and bass.
The songs are hard but not that hard and the production value is great. At best the on-stage antics look like a real live performance. The game includes some behind the scenes-videos and other fan extras. I really liked the "Metallifacts"-video trivia bits.
The setlist isn't that long (although you can get the whole Death Magnetic album on it by DLC) but If you're a fan you'll probably still play it once in a while for the ultimate rock star kicks. And if you're not a fan... Maybe you'll become one.
If you're a fan of music games, Metallica or both I'd recommend getting this, at least for a party rent. I promise you'll have a good time.
