I really enjoyed this. I love the play, and don't find it too talky at all. But that's just a matter of personal taste, I think. I love plays that are really dialogue-driven, especially when they involve intense philosophical and moral debates. For me, the evening totally flew by - didn't check my watch once, which is rare for me.
I agree there were some aspects of the direction that were distracting and heavy-handed, but I think Sullivan has a great sense of the basic drama of the piece. Each moment (of the actual scenes) was clear and engaging, and the show as a whole was very well-paced.
Loved the acting, especially Rashad and Davenport.
I saw the Donmar production last year, and while I found that one to be more well-directed, I thought Condola Rashad was superior to Gemma Arterton.
I will say though that I didn't care for the epilogue. They had a drastically shortened (and altered) version of it at the Donmar, and wish they had done the same thing here. That was the only scene that I really didn't like, but I think that's really Shaw's fault. Sullivan handled it as well as he could have, I think.