What to choose?
I use a cubase as well as a logic pro setup.
Both have their advantages and disadvantages but my current preference seems to go to the mac pro running logic pro 8.
In logic 8 everything is included (I have all the studio content discs installed. :) ) and everything is just within reach without having to load any vst instruments in a instrumentpanel. The sound is quite good straight out of the box, and I haven't run in to any performance problems either. I can build and build and won't run out of cpu power. The interface is cleverly layed out, and you'll always have all the controls you need are always just a mouse click away. (I guess the name logic is referening to the the way you work with it).
On the other hand there's cubase. The software I started out with many years ago on my first upgraded atari st 520. The power of the program then and still, is the simpel structure of the midi event editor and drum editor, Everything in the interface is familiar and I can find almost everything I need, without having to look for it. Although I still use quite an old version (3.0) of cubase for win xp. I don't think it is worth the upgrade price just yet to go to cubase 4, but now with lowering prices and the new release of cubase 5 I might look into it again. I think cubase 5 will take the good things out of logic and put it in an already familiar interface. The biggest problem of cubase is windows xp though, with all the different types of hardware you'll need general code, which could be slower than a (90%) hardware dedicated written software like os X. OS X is more stable and always feels responsive even after hours or even days of being online.
Most people know that windows (win xp sp3 not server) needs a least a reboot a day to stray fast and fresh. Memory just fills up in windows and every little util driver and other things you need to run windows uses cpu power.
Maybe I should look into cubase 5 for mac and get the best out of both worlds :D