Hi Theself,
The triple monitor setup may require triple sli gtx 580 3gb to get 60fps and that’s if sli were working perfect (maybe the next patch) to have settings at max.
Comparing CoD to a console port or FSX, which is 6 years old is a little unfair but your system will provide a playable experience I’m just not sure if it can do the 3 monitor setup yet without bringing the graphic settings down.
The choice between 3 monitors at reduced eye candy/resolution or one that looks great is yours
Below is some explanations of the settings tweaks by Luthier
http://forum.1cpublishing.eu/showthread.php?t=19819
For a full walk through of tweaks we can help you on the ATAG Ts3 coms too : ) just say when...