As long as they don't preserve New St Andrew's House in Edinburgh - ghastly empty hideous thing that has been squatting in the middle of one of the most beautiful cities in the world like some rectilinear concrete tumour.
[NB Not to be confused with St Andrews House - which is really rather nice.]
Every time I'm coming into London, I point out the ugliness of Trellick tower. I've never met anyone who ever thought it was anything but ugly. To boot, there's another one quite similar to it in the East End.
Edit: The tower block that is National Trust listed. http://www.telegraph.co.uk/culture/art/architecture/11129845... Designed by a Bond villain, of course.