I used GUIMiner for quite awhile and decided to give Phoenix a try a couple days ago. I just recently posted it into https://en.bitcoin.it/wiki/Mining_hardware_comparison
I am able to get 423 mh/s. Stales are a little higher but not too much more. Here are the settings I used if you're interested.
ATI Tray Tools, Clocks=995/331.25, WORKSIZE=128 BFI_INT AGGRESSION=11 VECTORS ,68C @ 65% Fan, HAF932 Case
One other thing to note. I can surf around on my pc and the hashing never drops below 410. With GUIMiner if I added -f0 I could get about 415 max and the pc was unusable.
Don't mean to hijack just figured I'd let you know.
Also, it's a Sapphire 2GB card in case that makes a difference.