I agree. David Bradley's performance is the best I have seen so far this year - he was better in this play than Michael Gambon and Donald Pleasance (in the 1980s revival anyway).
The acting was very direct and quite powerful. Shame about the play, I kept thinking it would be great to see the actors in something more interesting. I wasn't exactly bored, but I was vaguely glad when it was over and I could leave those characters and their tiny world behind.