My first thought is that you will need a boatload more HDD space than the single 200Gb disk you mentioned.

HD can run at about 80Gb per hour of footage. You do the math. Either way you go, you will def want at least two physical drives. One for the OS, say a 60 or 80Gb drive to install Windows and your s/w and then keep your 200 Gb drive for a video drive.

I have only used Premier Pro1.51 and Aspect HD and love them. I can't really offer any comparison to your other choice as I've not used it or even seen it tbh. I alrady had a certain $££ investment in Adobe s/w so the 'upgrade' to Aspaect HD was the obvious choice.

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