JClosed is correct. NOTHING beats Cubase MIDI-wise. Nothing!
So, if you do MIDI Orchestration, or work heavily with MIDI instruments
then Cubase is where you should live. MIDI in Sonar was ok, but very non-
intuitive in many ways. Things that were very simple in Cubase, are not so
simple in Sonar, or other DAW's for that matter. I'm sure those of you who
were "used" to Sonar's way of doing things may not agree. But the consensus
from MOST "heavy" MIDI users is that Cubase is the place to be.
I seriously can't believe that Pro Tools has maintained it's foothold ( I'm sure being HD helps it ).
It has always been severely lacking in the feature department. The ONLY thing that keeps it
where it is is the fact that most Engineers are used to working in it...so just keep
working in it, but not for features, but just "because" it's easier to do what you already know
than to "relearn" how to do things, even if, in some cases, it might be easier.