We have tested Transmutation, Curse Eater, Spell Power Cure and some other healing related sets.
They do no longer work on you and thus do not produce their effects while the blood channel is active.

The life steal that Wardens can produce for you to proc yourself also does not proc these effects. You do however still gain the health buff from wardens if I remember correctly.

I will say that my desire and my hype regarding vampire has greatly diminshed after evaluating all the drawbacks and the lackluster functionality of their abilities. I will still test it in a real environment when it goes live. But I tend to purge.