Bit late to this one but yes, I twice met him in a work context.
Professionally he was really knowledgeable, I hadn't expected that since we were working on quite an obscure area of public policy, but he asked quite intelligent questions, I wasn't expecting that.
Personally, he did that quite intense staring 'you are the only person in the world who matters to me right now' thing, I found that a bit uncomfortable but I can see how others might like it.
So on balance smarter than I imagined he would be but personally a bit of an actor, very aware of how he was coming across I think.
Carrie was with him when he met us the second time, we had no idea why she was there, she clearly wasn't staff. We wondered about that in the staffroom for a while after and then it all became clear. Not much of a date though, coming to spend the day with your lover in our office in the middle of nowhere. She must have been really keen.
He was very public school-ish, and since I'm the opposite I found myself reverting to my worst local accent. But that's my issue, not his, I have an unconscious tendency to do that when I'm around 'posh' people, they bring out the extreme working class in me.
It's been interesting to read other peoples' take on him.