SSD VS RAID

SSD will be way faster and for about $200 you can get a good 240GB one.

Yeah, the SSD wins, hands down. Order of preference / reliability:

Samsung 840 PRO / 830
OCZ Vertex 4
Intel 520
Samsung 840
Intel 335
OCZ Agility 4
Intel 330

SSD.
The main advantage of an SSD (especially as an OS drive) is its non-existent access times, which does not improve by RAID'ing Hard Drives. Also sequential read/writes are already faster than two RAID 0 HDD's.
Since I'm guessing capacity isn't going to be an issue, that nulls the main disadvantage of the SSD.

Use your cash to get a good 256GB SSD for the OS/programs/games and a single TB or 2TB hard drive for storage.