O love the steinberg shit for some reason... I've never used pro tools, but when I first used nuendo 1.0, I was sprung... it was so complicated, yet easy enough for me... I got cubase after that and I haven't looked any further yet.
I hear that protools is "proprietary" which would make me not want to touch it. With my Nuendo 2.0. I can do some shit in FL Studio, export as whatever, and mix it down fully via Nuendo...
But then again, protools might blow me away if I ever see it, not sure...
my 2 pennies for your thought.