Ok I did it anyway, now these were the settings I had on, everything was set to Normal or High with 16x AF, Triple Buffering, High Filter quality etc etc. I was getting about 25-30 FPS during a mission. Don't be mislead it is still very smooth for me and plays like I am getting 35 or more FPS. It looks superb even at medium to medium/ high.
The system I run on now is 2 GB ram 245Mhz, Opteron 180 @ 2.83 Ghz, BFG7800GTX stock. It is kind of a taxing game but it is very much playable and looks very good. I normaly run 4x AA without a prob.