Go does seem to have the best bindings of the platforms I listed, but the reason I put Go on the list is that go-qml hasn't been a commit to the repository in over a year, the mailing list traffic has significantly decreased, and seems to support rather old versions of Qt(though this may be wrong, the docs should be update or made more clear that it means the older version and later).
For me, the only drawback is not being able to expose a go object as a model, involving a bit of back and forth, but the rest is very very clean.