I am using Unity 2019.1, which MixedRealityToolkit should I use?

I download the two packages from this website:
https://github.com/Microsoft/MixedRealityToolkit-Unity/releases

Microsoft.MixedReality.Toolkit.Unity.Examples-v2.0.0-RC1.unitypackage
Microsoft.MixedRealityToolkit.Unity.Foundation.unitypackage

and I am using the latest version Unity 2019.1, after I import the two packages, there are some compile errors,

looks like the error is not hard to fix, but do we have a good enough version of MixedRealityToolkit for Unity 2019.1?

thanks