Still seems very case by case for me, on my 27" iMac with a 755M I ran both this morning, everything except driver overhead was still better on the OpenGL test then the Metal 2 test. Odd. I wonder how much is API side and how much is optimizing for the API, as I recon these low level APIs are more like a lot of rope for a developer to use as they will, not always an instant performance uplift. Wonder if this is using Direct to Display too, that's a big deal, lack of it always hurt MacOS GPU performance over windows since it was doing compositing and colour correction when it didn't need too, and compositing even when set to lower resolutions. https://arstechnica.com/gadgets/2017/09/macos-10-13-high-sierra-the-ars-technica-review/7/ And compute is even more different than graphics scores - the 2017 iMac scoring 115,000 in OpenCL compute was getting 50,000 on Metal compute on High Sierra. Hm.