Which MTG booster box should you buy?

well the eldrazi are amazing creatures so if you are into big creatures go for them but if you are looking for more general cards than go for M11 it all depends on what you want to play

personally i would go for M11 because many eldrazi cards are level up and aura and i am not to into them

but on the offside if you get an ererakul or ulamog or khozellik that is very cool