Can you really go to town with it? I have Digital Performer, Machfive, etc etc. But I'm doing it all on a Powerbook G4 and it's a little underpowered for those programs it seems. I'm imagining that Garageband (and the new one Garageband 2 that just came out) could be smoother to use/less of a resources hog? With Garageband can you loop record, have plenty of sends, busses and decent effects, etc etc.? thanks!