The reason the BFG is more is because it comes with a guaranteed overclock, which makes some people think it will be way better. Basically, your going to be getting a frame per second at whatever resolution, probably even less a lot of the time.
Get the eVGA, it'll save you $50, and think about buying an Artic Cooling Silencer, it'll make it way way quieter. Might have spent the same amount of money, but then you can overclock it better than the BFG, and it'll be a lot quieter. Or you could just save the $50
Or spend it in town