The sixth Preview release of 4.11 is now available to download from the launcher. Check out the new VR updates including Instanced Stero Rendering, where both the left eye and right eye are rendered at the same time, significantly cutting down on CPU workload.
To download Preview 6, head to the Epic Games Launcher and select the "Library" tab. If you already have a 4.11 Preview installed, simply hit the upgrade button. If not click "Add Versions", and choose 4.11 Preview 6.
You can read up on the fixes included in this release through this forum post from Stephen Ellis. Also be sure to have a look at the known issues list to see what's still outstanding. Please remember these Preview builds are for testing only, and should not be used for the active development of your project.