Then in July 2008 we'll have another "update" stating that ED is now doing a F-35 simulator for USA and they won't have enough time to complete BS untill Jesus arrives . . . :D
Gah! LOMAC 1.0 lost so much reputation because it was buggy as hell. They should have waited and released it when it was at 1.02 standarts. But, that's not how things work in gaming business I guess :)
Modern fighter doesn't suffer from the compression much, as GGTharos said. They've got around it with fully moving elevators so I don't think there's much of a problem :)
Your system is just fine. 7600GT would be almost a downgrade and 7800 just wouldn't worth the money. I'd say save some more money and wait for ATI vs Nvidia madness this summer :) Don't get anything below a 8800GT if you're really in a hurry.
You have to play around with FOV values to get a better view. If you're ok with stretched views, that's another problem though . . .
You may want to check this thread to do some corrections;
http://forum.lockon.ru/showthread.php?t=13573