As a performance test, I donned the VR head set and was pleased to find 90FPS even when the sun was going around the globe - updating the tone of approximately 1500 every half second. It was not laggy even during the updates.
This is a tower of the same instanced mesh actor with each instance given a custom value. The custom values are used to set a different Emissive value (in a checker box pattern).
Here is the same tower except the values are lighter towards the centre.