2x SLI GTX 580 enough?

[Kamui Zero]

I was wondering since I am building a New PC how is the framerate on a 1080p Maxed out Dx11 Hires texture Crysis 2 with 2x GTX 580 SLI'd?

I look at the benchmark Scores and 2 SLI GTX 580's beats the 590 by 5-10 frames, I am wondering the same on Crysis 2 since I want a machine that can handle Crysis 2 Maxed out with no problem.