However there are many reviews of Raid0 on the web which say the increase in speed for desktop users is hardly twice and is sometimes not noticeable even transferring files, unless you go by synthetic benchmarks. Raid0 is still software raid on most motherboards, and there is some cpu overhead because of this, since you are not talking about using a dedicated Raid card with onboard memory.
I had a Raid0 config myself with 74gig raptors and to be honest I did not notice much of an improvement, and the added risk is just not worth it, since if something goes wrong on one drive, then both are lost. Raid0+1 of course is a different story, but then you need more drives.
Personally I would rather a couple of 320gig or 400gig WD 7200 drives.