What's Better To Use for My System Drive?

Hi, I'm building an i7 920 rig for video editing. I'll be using a 1TB RAID0 for my media drive.

My question is for the operating system drive which will also hold the Adobe Studio install... I can afford either:

One 300GB WD VelociRaptor 10,000 rpm (w/ 16MB cache)

-or-

Two 750GB WD RE3 7,200rpm (w/ 32mb cache) in RAID0

My main goal is performance (not storage size, 300GB is plenty big enough for Windows 7 and Adobe). Would the 7200 pair in RAID0 be a better choice, especially sice each drive has 32mb cache? Or would the Raptor by itself still smoke the RAID0 config?

Thanks in advance!