Glad you enjoyed it. I almost went along yesterday with my boy as we had a day together without the other two. He's still a bit young for a photo exhibition though, so because he hadn't fallen asleep by the time the Balham Express (i.e. the Northern Line) hit the West End, we went to the British Museum instead where he ran around a lot and looked at swords and shields.
If I make it into the office this week I'll take a long lunch and pop over there.