Just for everyone who is dissappointed with ATI'S own. You can head over to Guru3D and download TwL modified drivers.

I am now using his newest set for crossfire setups (4.7) which is based on 10.9 and I fully recommend it.

HDMI scaling is ok and so far all games tested (Dirt2, Just cause2, Mass Effect2, Crysis, Alien Vs Predator) run very good and just feel smoother. Its quite amazing. I remember that in the days of the X1800XT and X1900XT I was using always Omega drivers + ATI Tray Tools, seems the pattern is still there. So again give it a try (BTW recommended to delete all old drivers, I have used Driver cleaner and no issue).