All looks good. If you are going to pay $175 for a 6850, i would try to get a used 5870 which would yield more performance than the 6850. Also, I have seen alot of post with problems from Asus boards plus the profile glitch which has been said to fry Cpu's. I would go with the asrock extreme or this gigabyte board.
With that said, as long as you buy some newer 1.5v RAM I doubt you will have problems with the latest bios on the Asus boards.