InstantVR 3.5 uses the native HTC Vive and Oculus Rift support in Unity 5.4 to provide a unified interface to those devices.
This video shows how to set up Unity to support either device and how you can use the SteamVR controllers or other input devices in combination with HTC and Rift.
General information on InstantVR can be found on my webpage: http://passervr.com
Please contact me if you have further questions or problems using HTC Vive or Oculus Rift with InstantVR.
Video using:
Unity3d Personal v5.4.0f3 (64-bit)
InstantVR v3.5.1