Need your advice guys

I'm planning to build a new Core i7 FSX rig and at the same time replacing my eVGA 8800GT 512MB SSC (700MHZ GPU, 2000MHz memory) with a XFX GTX285 card but now I wonder if it would be worth the extra approx $50 to get the eVGA GTX285 FTW Edition instead with a GPU running at 720MHz compared to the XFX card where the GPU is running @ standard 650MHz - do you think that will make any noticable difference in FSX?From what I've learned FSX isn't that dependent on the graphics card but more dependant on the CPU so that's why I figured I could save those extra bucks, I wise decision or am I stingy? Also worth mentioning is I'm planning to o/c my i7 to hopefully about 4 GHz if possible using watercooling so that's why I'm going for a GTX285 since I read anything below might become a bottleneck plus I'm using addons like REX etc using 4096 textures where a fast graphics card might become more important even in FSX.Thanks in advance for your input and comments!