I got mine a couple of weeks ago. Much better experience than with my prior evga 680i and my asus p5w dh deluxe (was running sli with modded drivers).
First, you will hit 500 FSB without issues. I ran my E6700 at 500x 7 FSB and it was stable for 12+ hours. Second, its designed for SLI so you have serious upgrade potential with your video card. Third the 8 phase power makes it very stable.
I'm very pleased and you will be as well. Try 500FSB x 7 multi at stock voltage and work your way up from there. With the new 0405 bios, kanaak at extremesystems hit 534 FSB on air stable (upped the voltage a bit)
here is the detailed analysis by kunaak with tips. it helped me
I haven't had a chance to test my new x6800 yet (Ran 7 x 500 for a quick test and it was perfect stable. I don't think i"ll be able to go too much higher without better cooling)