TLDR(150000 = 50,000 x 3 cave demo rocks instanced in UE4)
In lue of finding out about the instanced mesh component i updated to 4.6.1. So to test I updated my scatter script to use instanced geometry and put in some extreme values trying to test / crash the editor. When I enter 50K instances for the 3 Mesh base scatter objects jump to 6 minutes to see the end result. It was interesting seeing the power of instances.
Anyone else experimented with instances yet?