Digital Performer all the way for mac. You can't beat the submillisecond MIDI timing. It has the tightest timing out of all sequencers and the plug-ins are great. I originally started with Cubase so I was reluctant to relearn a sequencer. However I'm so glad I did. DP-3 is a dream. The nice thing about it is that you can do non-destructive fade-in and fade-outs. What I remember about Cubase 5.0 is that once you performed a fade out, you couldn't undo it down the line. In DP-3 you can delete your fades. Also the bounce to disk feature is nice. Say you have a track with too many effects going, you can bounce the track to another one and then delete the track with all the effects to save processing power. Also the new multiple undo branched history in DP 3.11 is very useful. Can you do these things with Cubase SX? I know you couldn't do them with 5.0 and I wonder if they changed all that yet.