Yes me too, I'm interesting to use tri-screen monitors or buy samsung 27'' I don't know yet, The best way will be HD5850 or 5870 if you have enough money.
Me I have Core I7 920 o/c 3.5 ghz and I saw a huge difference in comparison to my E7200 o/c 3.8 ghz Anyway your CPU is good for FSX and if you can o/c it that will be still better.