Mac, everything works perfectly, 1080p and lossless audio dolby dts I have all that going on, what appreciate without problem.
Under windows I had some small problems (I have an iMac 27 "2011 with the 6950M 2GB), the screen did not satisfy all (sub scanning) and the sound did not come out in surround sound. For the sub scanning of the Catalyst screen center should be set up and configure, and sound DOWNLOADING the latest drivers from ATI (me was the patch for ATI Rage me accidentally solved that problem) HDMI output will be detected and even with 5.1 7.1.
I recommend this adapter, which has an aluminum finish to stay in shades of your mac and its quality which for the moment I was not disappointed at all, the problem under windows from drivers and not the adapter.