My experience is pretty limited, but I am with Yixin on the variation point. I saw a couple bottles around NYC over the last year that I thought were a little tired. It's possible that I wasn't patient enough and the wine was just closed, but I suspect that freshening it up with some 09 would have helped. But I have also been lucky enough to taste a good bottle once or twice, and those seem like they will last a long time, and maybe even develop positively.
Vaughn, I have no immediate plans to be in London, but if I get shipped over there for work at all, then I will be glad to explore this question with you.