Battle of the Logics

As most of you may know by now, I am obsessed with creating music. Up until the vast majority of my pieces have been created with Garageband. But now I'm beginning it's a little too amateur for my taste and the features are now very limited.

I've heard of FruityLoops, and the Logic programs.

There's Logic Studio, Logic Express and Logic Pro.

Can anybody tell the difference between them? Which is best? Are they good?

THANKS