Hi,
TestMetal issues:
Selecting multiple objects (more = worse) results in laggy viewport, at some point it exceeds capability to display and freezes, then black viewport.
Btw - I opened a 1GB file with complex geometry + meshes on a 2020 MacBook Air. A bit laggy, but normal. → Once I typed testmetal… what the… I never experienced Rhino with such a file in 60Hz fluid in Perspective Shaded, Rendered or Arctic. Even my RTX3090 on Windows doesn’t achieve this. Compliments.
It’s a work in progress. Chill!
Very interesting reply
You think so? 
it’s pretty good already, when they finish hooking up the rest of the pipes it should be really great. It’ll be fantastic to get properly fast display performance on the mac.
Thanks for the bug report; there is a part of the selection code that we are going to work on soon that should help fix this issue (it’s also why selection is questionable at best on iRhino). We discovered recently that we are using OpenGL during selection to generate some data used for selection and this needs to be rewritten in metal.
thanks! it already is SO amazing to use. 
yes, I think you got me wrong. A 3090 is a pretty good graphics card, together with an amd ryzen. and what I was saying is that with testmetal, my macbook air is able to achieve way better display performance than this powerful windows machine.
Sorry. 