RD600 isnt a bad board by any stretch, however you arent guaranteed to it 500FSB without some serious voltage bumps, and probably something like an HR-05 for the NB.
I love all the voltage options avaliable, likewise with all the memory setting to tweak the best OC out of your rig, however it doesnt like running Sync with the CPU over a certain limit..... i can get 570Mhz Async, and it wont go 438Mhz sync on the same settings.
Still, DDR2-1140 @ 5-5-5-18, with 3.5Ghz cpu clock isnt bad for my hardware setup, so im not dissapointed. Not the best mobo for a E6300 though i would say, though the E4300 sshouldnt have so many probs with high FSBs.
Synthetic benchies are lower, but tbh unless you are measuring your equipment by the benchies you can push out, then its not a prob, real world performance is roughly on par. Hopefully a future BIOS will improve the performance somewhat (DFI have a beta out, but im wiating till it's finalised, and the last full release was December, so they have had time to tweak).