Its worth mentioning that the show room demo in the oculus config tool is a very performance friendly scene.
You can actually access the the FBX file for this scene and import them into unreal, the reason the performance is so good is that the texturing and the lighting are all baked into just a couple of textures meaning that the scene is effectively an unlit scene with unlit materials…no lighting, no PBR, no special effects, by doing this the performance will be rock solid meaning less latency.
I have remade the scene in Unreal and they behave identically.