Studies have shown that gaming really doesn't benefit from an SSD.
Programs will load faster, and well as maps and such, but that's about it.
But, to keep things simple, go with a single SSD. TRIM is not supported with SSDs as part of a RAID array. There are ways around it, but basically you will lose 15-20% of the available space to compensate for the loss of TRIM. TRIM is part of Windows 7, which helps a SSD drive to "self-optimize."
BTW: That's a great rig!