Hello, I'm going to upgrade my harddrives soon. I use about 300gb of space in my hd, and want to upgrade to a raid-0 (2x1tero) hd configuration... and use my current 500gb drive for my time machine hd. Will that work up until i approach 400-500 gb? Or do i need a 2 tero hd for time machine to work at all? I am not that concerned with having time machine go back too far, i just want an uptodate backup mostly... thanks, r.