Although this is a pretty old post, just stumbled across it while looking for comparisons of pro tools and cubase. I'd have to say it's very mac-biased and the fact you haven't covered cost is a major flaw in the comparison. I recently spec'd out a high performance DAW PC (quad core CPU, 6gb RAM, 3x1tb HDD, etc etc), which I'm building myself (not as hard as it sounds). Because my university is very keen on the old mac/protools combo I just went to look at a mac of the same spec. The PC came to £970, including WIn7 pro 64bit OS and dual 22" displays. The Mac equivalent of the same spec was around £3,700. Not withstanding the PC had a soundproofed case, passively cooled GPU and other silent-running hardware installed specifically for audio use. When you're looking at saving over 2.5 grand on your machine - money which could be spent on a better audio interface, monitors, controllers, instruments, software or microphones to name but a few studio needs - I personally feel the saving you make on high end systems is well worth the research needed to build a system from scratch.