The 4870X2 does indeed post decently higher AVG FPS, bit ive had 2 in CF before and the MIN FPS in a lot of the games i played (GRID, COD4, CRYSIS, the list goes on) was par or lower than my 1 oc GTX260 that replaced them, and i never looked back. i dont care for frame-spikes, but i do care about frame dips, and with Dual GPU, it happens a plenty.
1xGT200 = pwnage, thats some math for ya, go buy one already