Yes, so close...

Great user interface, great concept, great value (with all the synths and effects).

However, I do own a hexacore 2013 Mac Pro with 64GB RAM. Even with such a fast workstation, I was often missing a beat (quite literally) with MainStage due to unexplained CPU spikes: CPU use would stay around 25% and then suddenly (even when I was not playing anything at all) would peak around 200% the next moment causing very annoying drop outs and delays. This makes the application completely useless for professional use (and even for hobbyist use). Judging by what I read on the internet, I am not alone with this problem.

Griffon about MainStage