I'm still not sure who LEGO Rock Band is for. I'm sure there's somebody out there that owns Rock Band 2, but doesn't want to admit he listens to metal songs, and has a couple kids that refuse to play anything without cartoony characters, and a mother in law who is so bad at rhythm games she needs them to practically play themselves. Plus this guy likes to spend full price for half a game. Lego Rock Band is perfect for you, dude.
Trying to tell you whether or not you should buy this game is complicated. Honestly it might require an extensive flowchart. I can tell you right off the bat that ...