I was thinking the HIS version because of the 840 MHz core clock and the 1280 MHz Memory as well as overclocking right out of the package, but it lacks 2 fans like the Sapphire and XFX model have.
The Sapphire model is lacking a Mini DisplayPort, which leaves the other two PowerColor and XFX at the same specs.
+1 for the XFX version for the double lifetime warranty. The Sapphire one would be my close second. I have the sapphire one, and it is amazing. Very quiet, and overclocked to 900mhz with 1350 mhz mem. However I would still pick the XFX over it. why? the warranty and I like the way it looks better.