Are V-Ray 5 materials backwards compatible?

[Streetwise]

If materials are created using V-Ray 5, would they be able to be opened in V-Ray NEXT and rendered? Any issues to be aware of?

[hermit.crab]

Library materials from V-Ray 5 will render fine in NEXT, however, without the newly introduced parameters (VRayUVWRandomizer, Coat, Sheen) if used in a given material. Differences are expected in those materials.