Scotch, that's just about the same as my build I put together last year, except I got a different psu and I got the overclocked MSI 5850, and a different model of Asus mb. You'll want a bigger psu I think, if I remember right the mb I had wanted 600 or 650 as the bare minimum.  At any rate, it'll do the job nicely for you I think.  Don't forget that you'll want a powered usb hub for your stick/throttle/pedals.  I kinda lucked out and got a really good Samsung 22 inch monitor when CompUSA was going out of business, for not much over a hundred bucks.  
Dug up the thread where I posted it...  ASUS M4A79XTD EVO AM3 AMD 790X ATX
                                   
                                   AMD Phenom II X4 955 Black Edition Deneb 3.2GHz Socket AM3 125W Quad-Core Processor
                                   G.SKILL Ripjaws Series 4GB (2 x 2GB) 240-Pin DDR3 SDRAM DDR3 1333 (PC3 10666)
Very similar rigs and this one runs it like a champ, everything possible on and nary a problem.